EIGHTEENTH INTERNATIONAL CONFERENCEON
LIQUID AND AMORPHOUS METALSLAM 18September 4-7&

Online September 8-9, 12

2022

EIGHTEENTH INTERNATIONAL CONFERENCEON
LIQUID AND AMORPHOUS METALSLAM 18September 4-7&

Online September 8-9, 12

2022

CONFERENCE ORGANIZATIONORGANIZING COMMITTEE
Chair (General): M. Inui (Hiroshima Univ.)
Chair (Program): F. Shimojo (Kumamoto Univ.)
Co-Chair:S. Hosokawa (Kumamoto Univ.)
Co-Chair:H. Kato (Tohoku Univ.)
Y. Kajihara (Hiroshima Univ.)
S. Munejiri (Hiroshima Univ.)
S. Ohmura (Hiroshima Inst. Tech.) S. Kohara (NIMS)
H. Masai (AIST)
T. Morishita (AIST)
Y. Kawakita (J-PARC)
K. Matsuda (Kumamoto Univ.)
S. Tahara (Univ. of Ryukyus)
H. Shimakura (Niigata Univ. of PALS)
T. Usuki (Yamagata Univ.)
T. Iwashita (Oita Univ.)
J. Saida (Tohoku Univ.)
T. Otomo (KEK)
K. Fuchizaki (Ehime Univ.)
K. Kimura (Univ. of Tokyo)
A. Chiba (Keio Univ.)

INTERNATIONAL ADVISORY BOARD
A. Di Cicco (Italy)
B. Gelchinski (Russia)
S. Hosokawa (Japan)
H. Liu (China)
P. Popel (Russia)
K. F. Kelton (USA)P. S. Salmon (UK)
T. Scopigno (Italy)

C. D. Dalian (China)
D. J. Gonzalez (Spain)
M. Inui (Japan)
W. C. Pilgrim (Germany)J. F. Wax (France)
D. L. Price (France)
F. Shimojo (Japan)
M. Vasin (Russia)

INTERNATIONAL PROGRAM COMMITTEE
T. Bryk (Ukraine)
F. Demmel (UK)S. De Panfilis (Italy)
V. Giordano (France)
D. Holland-Moritz (Germany) N. Jakse (France)
J. Z. Jiang (China)
K. Khishchenko (Russia)
B. Ruta (France)
W.Schirmacher (Germany)
V. Sidorov (Russia)
M.-L. Saboungi (France)
P. Svec (Slovak Republic)
H. Kato (Japan)

2

SPONSOR
THE KAJIMA FOUNDATION（鹿島学術振興財団）
JSMS Committee on Metallic Glasses（日本材料学会金属ガラス部門委員会）
ELECTRIC TECHNOLOGY RESEARCH FOUNDATION OF CHUGOKU（中国電力技術研究財団）

SPONSOR Company
Heraeus K.K.

MAKABE R&D Co.,LTD

SCOPE OF CONFERENCE
Since the 60s the state-of-the-art in the field of liquid and amorphous metals and alloys is thefocus of an international conference, the “Liquid and Amorphous Metals conference” (LAM),
which is in its 18th conference. Born as a conference on liquid metals in 1966 at Brookhaven,since 1980 it has been renewed including amorphous metals (1980, Grenoble, France) and thenhas continued a three years basis, with the last three editions held in Beijing, China, in 2013,
in Bonn, Germany, in 2016 and in Lyon, France, in 2019.
The aim of the LAM conferences is to bring together scientists working in the field of liquid andamorphous metals in order to discuss new advances and future directions in this intriguing fieldof condensed matter physics, chemistry and materials sciences. Although primarily aimed at
discussing the hottest topics in liquid and amorphous metals including semiconductors, molten
salts, quasicrystals, complex systems, and some non-metallic systems such as molecular glasses,
polymers, and colloids have in the past found their place in the conference, with the aim ofstimulating discussions and brainstorming.
The conference includes the following topics:- Structure- Dynamics- Atomic transport and diffusion phenomena- Microstructure – heterogeneities- Modelling and simulations- Electronic structure and transport- Thermodynamics.
- Surface and interfacial properties- Magnetic properties- Mechanical properties- Solidification- Glass transition- Metal-nonmetal transition- Amorphous and quasicrystals- Exotic phenomena- Experiments performed in space- Hyper-order investigation- Industrial applications
3

INFORMATION ON LOCAL CONFERENCECONFERENCE VENUEJMS Aster Plaza Hiroshima International Youth House
Kakomachi 4-17, Naka-ku, Hiroshima City, Hiroshima pref. 730-0812, Japan
TEL: 082-244-8000

HBG Hall (Welcome party, Buffet Lunch)

From JR Hiroshima station
Street Car (190 JPY)

: ① to Kamiyacho-keiyu Ujina : getting off at Shiyakusyomae and 600 m: ⑥ to Eba : getting off at Funairicho and 400 m

Bus (190 JPY)

Line 24 of Hiroshima Bus: to Yoshijima eigyosyo or to Yoshijima Byoin: getting off at Kakomachi and 200 m

Taxi (about 1,200 JPY)

: about 15 min

From Bus Center
1.5 km on footTaking Street Car or Bus above at Kamiyacho (Be careful, several stops to different destinations)4

Hiroden (Street Car) route map

Example of required time5JMS Aster Plaza Hiroshima International Youth House

Attention: Please come to Registration desk at first before going to Welcome
Party open at 18:00 (close at 20:00).
REGISTRATION
Registration desk at JMS Aster Plaza (ground floor) will be open during the following times:
September 4
15:00-18:00
September 5-6
09:00-18:00
September 7
09:00-16:00

MEALS
Buffet Lunch is included in the registration fee.

COFFEE BREAK
Coffee break is supplied at Citizen’s Gallery (poster session room) on the ground floor in Aster
Plaza.
6

ORAL SESSIONS
Oral presentations are conducted at Medium Hall upstairs in JMS Aster Plaza.
Please keep your allocated time that includes discussion & comments.
Total duration:
Plenary Speaker: 40 min
Invited Speaker: 30 minCommittee Member Talk
: 30 min
Local Committee Member Talk
: 25 minGeneral: 20 minOnline participants can watch live steam of oral session but please send the questions andcomments to the presenter by e-mail.

POSTER SESSION
Poster session is conducted at Citizen's Gallery on the ground floor in JMS Aster Plaza. The
area for each poster is about 1200 mm × 1800 mm. We are assuming a poster size of about 900
mm × 1200 mm. The poster can be mounted at the allocated area from 15:00 on 4th September
till 15:00 on 7th September. We provide permitted tapes to fix a poster on the wall. Never use

pushpins and your own tapes to do it.

SOCIAL PROGRAMWELCOME-RECEPTION-PARTY
Date: Sunday, September 4, 2022
Time
: 18:00-20:00
Place: Café & Restaurant in HBG HallCONFERENCE DINNER (BANQUET)
Date: Wednesday, September 7, 2022
Boarding Time : 18:35Time: 18:50-21:00
Place: Cruising by GingaFee: 11,000 yen

7

INFORMATION ON ONLINE CONFERENCE
ORAL SESSIONS
We are preparing zoom for the online presentation. Please see notes in ORAL SESSIONS above.

POSTER SESSIONS
Online poster session includes online posters plus most of posters in Local conference. We arepreparing the web site to upload a poster of about 900 mm × 1200 mm whose size is 20 MB
maximum. Files of pdf and jpeg per poster (the name should be poster number.pdf and poster
number.jpg) should be submitted to a file exchanged system whose URL will be announced toeach presenter. When your file becomes larger than 20 MB, please contact us. Short presentation(within 5 min, within 5 slides including a cover sheet) is programmed for every poster. The shortpresentation is conducted using zoom of oral presentation. Please prepare slides for shortpresentation. Discussion of each poster can be done using breakout room in zoom or the zoom
prepared by the presenter.

MANUSCRIPTS
The special issue on18th International Conference on Liquid and Amorphous Metals (LAM18)
is published by J. Phys.: Condensed Matter, similarly to LAM17. The deadline of the submission
will be in November after LAM18 conference. All relevant researchers, regardless of whether
they participated in LAM18 or not, are eligible to present their research in the special issue.

8

Memo

9

Session A2

Coffee BreakCoffee Break

Poster Session PS1

15:50-17:50

Session A5

Coffee BreakAri Paavo Seitsonen

Alfred Q.R. Baron

Session A4

Takeshi Egami

Jens Rüdiger Stellhorn

16:40-17:00

Poster Session PS2
16:40-18:40

18:35-

16:20-16:40

15:50-16:20

15:30-15:50

15:00-15:30

14:30-15:00

14:00-14:30

12:45-14:00

12:25-12:45

12:05-12:25

11:35-12:05

11:15-11:35

10:55-11:15

10:30-10:55

10:00-10:30

9:20-10:00

Coffee BreakKohei Shimamura

Committee Yukinobu Kawakita

Session A7

Coffee BreakYoshifumi Sakaguchi

Committee Ayano Chiba

InvitedSession A6

Lunch

Hiroki Naruta

Junpei T. Okada

Committee Yukio Kajihara

InvitedPlenary
Session A8

Yang Ren

Hikaru Kitamura

Akihide Koura

Wolf -C. Pilgrim

Session A11

Coffee BreakTakeshi Wada

Robert Maaß

László Pusztai

Boarding / DinnerInvitedInvitedInvitedInvitedSession A10

Lunch

Hinata Hokyo

Fabio IesariCommittee Jean-François Wax

Session A9

Coffee Break

Yoichi Nakajima

Committee Satoshi Ohmura

Committee Andrea Di Cicco

Plenary

Wednesday 7th, September

16:20-16:40

16:00-16:20

15:35-16:00

15:15-15:35

Rui Yamada

15:10-15:30

15:30-15:50

14:55-15:15

Peter Michael Derlet

14:50-15:10

14:00-14:30
14:30-14:55

Noel Jakse

Eloi Pineda

Invited14:30-14:50

14:00-14:30

12:15-14:00

Lunch

12:05-14:00

Session A3

11:55-12:15

Yusuke Ohashi

11:35-11:55

11:10-11:35

10:50-11:10

10:30-10:50

10:00-10:30

9:20-10:00

Tuesday 6th, September

11:45-12:05

11:20-11:45

11:00-11:20

Masato Ohnuma

Giancarlo Jug

Session A1

Xun-Li Wang

Introduction

Committee Junji Saida

Invited

10:10-10:40

10:40-11:00

Plenary

9:30-10:10

9:20- 9:30

Monday 5th, September

Local Conference Programme at a GlanceSession R2

Coffee BreakInvited

21:20-21:50
14:20‐14:50
21:50-22:10
14:50‐15:10
22:10-22:30
15:10‐15:30
22:30-22:40
15:30‐15:40

Paul Laffont

Xiao-Dong Wang

Dmitri V. Louzguine

Session R5

Coffee Break

Katsuki Hayashi

Xinguo Hong

Yohei Onodera

Session R4

Coffee BreakKazuki Mitsui

Shuang Zhang

Chuang Dong

Session R3

Meal BreakNicolai Lukas GrundNeta Ellert

Committee Dirk Holland Moritz

Invited

22:40-23:00
15:40‐16:00
23:00-23:20
16:00‐16:20
23:20-23:40
16:20‐16:40

Luis E. González

Session R1

Committee Taras Bryk

Invited

20:00-20:30
13:00‐13:30
20:30-20:50
13:30‐13:50
20:50-21:10
13:50‐14:10
21:10-21:20
14:10‐14:20

17:10-17:40
10:10‐10:40
17:40-18:00
10:40‐11:00
18:00-18:20
11:00‐11:20
18:20-20:00
11:20‐13:00

JST
CEST
16:00-16:30
9:00‐9:30
16:30-17:00
9:30‐10:00
17:00-17:10
10:00‐10:10

Thursday 8th, September

22:20-22:40
15:20‐15:40
22:40-23:00
15:40‐16:00

21:10-21:30
14:10‐14:30
21:30-21:50
14:30‐14:50
21:50-22:10
14:50‐15:10
22:10-22:20
15:10‐15:20

20:00-20:20
13:00‐13:20
20:20-20:40
13:20‐13:40
20:40-21:00
13:40‐14:00
21:00-21:10
14:00‐14:10

17:25-18:20
10:25‐11:20
18:20-19:00
11:20‐12:00
19:00-20:00
12:00‐13:00

16:40-16:55
9:40‐9:55
16:55-17:15
9:55‐10:15
17:15-17:25
10:15‐10:25

G. M. Bhuiyan

Dmitrii Fleita

Session R10

Coffee BreakYanhui Li

Vadim B.Vorontsov

Shuang Ma

Session R9

Coffee Break

Tianding XuLoïcia Gaudilliere

Shuai Wei

Session R8

Meal Break

Poster Session RPS1

Poster Short Presentation

Session R7

Coffee BreakFan Yang

Corporate Webinar

JST
Friday 9th, September
CEST
16:00-16:40
Plenary Jian-Zhong Jiang
9:00‐9:40
Session R6

Online Conference Programme at a Glance

22:10-22:40
15:10‐15:40
22:40-23:00
15:40‐16:00
23:00-23:10
16:00‐16:10

21:00-21:30
14:00‐14:30
21:30-22:00
14:30‐15:00
22:00-22:10
15:00‐15:10

20:00-20:30
13:00‐13:30
20:30-20:50
13:30‐13:50
20:50-21:00
13:50‐14:00

17:10-18:00
10:10‐11:00
18:00-18:40
11:00‐11:40
18:40-20:00
11:40‐13:00

JST
CEST
16:00-16:30
9:00‐9:30
16:30-17:00
9:30‐10:00
17:00-17:10
10:00‐10:10
Session R12

Coffee Break

Nikolay Chtchelkatchev

Jörg Behler

InvitedInvitedInvitedInvited

Closing

Nico Neuber

Osamu Yamamuro

Session R15

Coffee Break

Kostya Trachenko

Takashi Odagaki

Session R14

Coffee BreakAyu Irie

Michele Ceriotti

Session R13

Meal Break

Poster Session RPS2

Poster Short Presentation

InvitedInvitedSession R11

Monday 12th, September

Local Conference Programme

LAM-18 Conference
Local Conference Programme
Day 1 - Monday 5th, September 2022
9:20-9:30

Welcome/Introduction

Organizers

9:30-10:10

Plenary Session I

Chair: Masanori Inui

Plenary Talk

Xun-Li Wang

Medium-range Order and Cluster Connectivity

City University of Hong Kong,
China

10:10-11:00 Session A1

PL1

Chair: Junji Saida

Structural Properties of Glasses
10:10-10:40 Invited Talk
The Intermediate-Range Structure of Glasses as seenfrom their Magnetic Properties and Under an Optical
Microscope
10:40-11:00 Structural Origin of Temperature Memory Effect ofQuenched Strain in Metallic Glasses

Giancarlo Jug

IL1

Università dell’Insubria, Italy

Masato Ohnuma

O1

Hokkaido University, Japan

11:00-11:20 Coffee Break
11:20-12:05 Session A2

Chair: Noel Jakse

Synthesis of Metallic Glasses
11:20-11:45 Local Committee Member Talk
Synthesis and Mechanical Property of Highly Structure
Controlled Metallic Glasses by Thermal Rejuvenation
Technique11:45-12:05 High-entropy design and its influence on glass-forming
ability in Zr–Cu-based metallic glass

Junji Saida

CL1

Tohoku University, Japan

Yusuke Ohashi

O2

Tohoku University, Japan

12:05-14:00 Lunch
14:00-15:30 Session A3

Chair: Giancarlo Jug

Dynamic Properties of Metallic Glasses
14:00-14:30 Invited Talk
Dynamic heterogeneities in undercooled metallic alloys

Noel Jakse

IL2

Université Grenoble-Alpes, FranceLocal Conference Programme

14:30-14:50 Relaxation dynamics of glass forming metals: Study of
aging anelasticity and supercooled liquid behavior in a
ZrTiCuNiBe alloy

Eloi Pineda

O3

Universitat Politècncia deCatalunya, Spain

14:50-15:10 Emergent structural heterogeneity and it’s effect onviscosity and transport in a model binary metallic glass

Peter Michael Derlet

15:10-15:30 Creation of Three-Dimensional Relaxation State
Gradient in Zr50Cu40Al10 Metallic Glass Through a
Thermal Process

Rui Yamada

O4

Paul Scherrer Institute, Switzerland

O5

Tohoku University, Japan

15:30-15:50 Coffee Break
15:50-17:50 Poster Session PS1

Day 2 - Tuesday 6th, September 2022
9:20-10:00

Plenary Session II

Chair: Shinya Hosokawa

Plenary Talk

Takeshi Egami

How the Liquid Structure is Formed; Bottom-up, Topdown, or Both?

University of Tennessee, USA

10:00-10:50 Session A4

PL2

Chair: Yukio Kajihara

Dynamic Properties
10:00-10:30 Invited Talk
Hydrodynamic Interaction Between Quasi-elastic andAcoustic Modes Observed by Inelastic X-Ray
Scattering
10:30-10:50 Ab initio Study of Collective Excitations in Liquid Sb

Alfred Q.R. Baron

IL3

RIKEN SPring-8 Center, JapanAri Paavo Seitsonen

O6

École Normale Supérieure, France
10:50-11:10 Coffee Break
11:10-12:15 Session A5

Chair: Alfred Q.R. Baron

Phase Transition in Liquids
11:10-11:35 Local Committee Member Talk
Interpretation of thermodynamic anomalies of liquidwater in terms of critical fluctuations

Yukio Kajihara
Hiroshima University, Japan

CL2

Local Conference Programme

11:35-11:55 Phase relation between supercooled liquid andamorphous Silicon

Junpei T. Okada

O7

Tohoku University, Japan

CancelledO8

11:55-14:00 Lunch
14:00-15:15 Session A6

Chair: Yukinobu Kawakita

Structure I
14:00-14:30 Invited Talk
Structure of amorphous Cu-Ge-Te and the implications
for its functionality
14:30-14:55 Local Committee Member Talk
X-ray and neutron diffraction of semi-crystalline
isotactic poly (4-methyl-1-pentene) with alkane
absorption

Jens Rüdiger Stellhorn

IL4

Hiroshima University, Japan

Ayano Chiba

CL3

Keio University, Japan

14:55-15:15 Direct observation of concentration fluctuations in Au-Si Yoshifumi Sakaguchi
O9
eutectic liquid by small-angle neutron scattering
Comprehensive Research
Organization for Science andSociety (CROSS), Japan
15:15-15:35 Coffee Break
15:35-16:20 Session A7

Chair: Jens R. Stellhorn

Dynamic and Transport Properties
15:35-16:00 Local Committee Member Talk

Yukinobu Kawakita

CL4

Structural Relaxation in Complex Liquid Metals
Japan Atomic Energy Agency,
Japan
Antimony and Bismuth by Means of Coherent QuasiElastic Neutron Scattering and Time -Space Correlation
Function
16:00-16:20 Estimating Thermal Conductivity of Silver
Chalcogenides Using Machine-Learning Interatomic
Potentials
16:20-16:40 Coffee Break
16:40-18:40 Poster Session PS2

Kohei Shimamura

O10

Kumamoto University, Japan

Local Conference Programme

Day 3 - Wednesday 7th, September 2022
9:20-10:00

Plenary Session III

Chair: Hidemi Kato

Plenary Talk

Yang Ren

Supercritical Elasticity and Structural Entanglement ofMulticomponent alloys

City University of Hong Kong,
China

10:00-11:15 Session A8

PL3

Chair: Jean-François Wax

Liquids and Glasses under Pressure
10:00-10:30 Committee Member Talk

Andrea Di Cicco

CL5

Investigation of local structural changes in GeSe2 glass University of Camerino, Italy
under ultra-high pressure
10:30-10:55 Local Committee Member Talk
Bonding and structure of liquid iron-light-elementoxygen ternary alloys under high pressure: molecular
dynamics simulations
10:55-11:15 Inelastic X-ray scattering measurements of liquid Fe-S
at high pressure

Satoshi Ohmura

CL6

Hiroshima Institute of Technology,
Japan

Yoichi Nakajima

O11

Kumamoto University, Japan

11:15-11:35 Coffee Break
11:35-12:45 Session A9

Chair: Andrea Di Cicco

Properties under Pressure and Shear Strain
11:35-12:05 Committee Member Talk
Simulation study of the collective excitations in liquidsodium under high pressure
12:05-12:25 Structure of liquid Cd under high-pressure condition

Jean-François Wax

CL7

Université de Lorraine, France

Fabio Iesari

O12

Aichi Synchrotron Radiation
Center, Japan
12:25-12:45 Ab initio simulation for the ductility mechanism of silver
chalcogenides

12:45-14:00 Lunch

Hinata Hokyo

O13

Kumamoto University, Japan

Local Conference Programme

14:00-15:30 Session A10

Chair: Wolf -C. Pilgrim

Properties of Metallic Glasses
14:00-14:30 Invited Talk
Reverse Monte Carlo modeling: state of affairs andapplications to metallic glasses
14:30-15:00 Invited Talk
Long-time and intermittent structural evolution of
metallic glasses

15:00-15:30 Invited Talk
Decoupling between thermodynamic and dynamical
glass transitions in high-entropy metallic glasses

László Pusztai

IL5

Wigner Research Centre forPhysics, Hungary
Robert Maaß

IL6

Federal Institute for Materials
Research and Testing (BAM),
Germany
Takeshi Wada

IL7

Tohoku University, Japan

15:30-15:50 Coffee Break
15:50-17:00 Session A11

Chair: László Pusztai

Structure II
15:50-16:20 Invited Talk
Structure Determination in a new Type of Amorphous
Molecular Solids with Extreme Nonlinear Optical
Properties

Wolf -C. Pilgrim

Philipps-University of Marburg,
Germany

16:20-16:40 Static Structure of Liquid Ag2Se Based on Molecular
Dynamics Simulations Using Artificial Neural Network
Potential

Akihide Koura

16:40-17:00 Semianalytic Formula for Multiphonon Thermal Diffuse
Scattering in Solids

Hikaru Kitamura

17:00-18:35 Free time
18:35-

Boarding

18:50-

DinnerIL8

O14

Kumamoto University, Japan

Kyoto University, Japan

O15

Online Conference Programme

LAM-18 Conference
Online Conference Programme
JST
CEST

Day 4 - Thursday 8th, September 2022

16:00-17:00 Session R1
9:00‐10:00
Structure and Dynamics of Liquids I

Chair: Kazuhiro Matsuda

16:00-16:30 Invited Talk
9:00‐9:30
Dynamic properties of liquids of interest in nuclear
energy production: liquid Li-Pb alloys and molten UO2Luis E. González

16:30-17:00 Committee Member Talk
9:30‐10:00
Origin of Positive Sound Dispersion in Simple Liquids
and Liquid Alloys

RIL1

Universidad de Valladolid, Spain

Taras Bryk

RCL1Institute for Condensed Matter
Physics of NASU, Ukraine

17:00-17:10 Coffee Break
10:00‐10:10
17:10-18:35 Session R2
10:10‐11:35
Structure and Dynamics of Liquids II

Chair: Tomoko Mizuguchi

17:10-17:40 Committee Member Talk
Dirk Holland Moritz
RCL2
10:10‐10:40
Chemical short-range order in undercooled Cu-Ni melts Institute of Materials Physics inSpace, Germany
17:40-17:55 Corporate Webinar Talk
10:40‐10:55
Company Introduction and Gas Atomization
Technology
17:55-18:15 The Short-Range Order in Liquid Water
10:55‐11:15

18:15-18:35 Impact of sulfur addition on the structure and dynamics
11:15‐11:35 of Ni-Nb alloys

Teppei Ishikawa

RCW0

MAKABE R&D Co.,LTD
Neta Ellert

RO1

Ben-Gurion University of the
Negev, Israel
Nicolai Lukas Grund

RO2

Institute of Materials Physics inSpace, Germany

18:35-20:00 Meal Break
11:35‐13:00
20:00-21:10 Session R3
13:00‐14:10
Structure and Dynamics of Non-Crystalline Materials I

Chair: Tetsuya Morishita

20:00-20:30 Invited Talk
13:00‐13:30
Cluster-plus-glue-atom Model and the Thus-obtained
Composition Genes for Metallic Glasses

Chuang Dong

RIL2

Dalian Jiaotong University, China

Online Conference Programme

20:30-20:50 Composition Optimization Based on Cluster-plus-glue13:30‐13:50 atom Model for Bulk Metallic Glass Zr55Cu30Al10Ni5

Shuang Zhang

20:50-21:10 Colorless and high refractive SnO- and Sb2O313:50‐14:10 containing borosilicate glasses

Kazuki Mitsui

RO3

Dalian Jiaotong University, China
RO4

Ehime University, Japan

21:10-21:20 Coffee Break
14:10‐14:20
21:20-22:30 Session R4
14:20‐15:30
Structure and Dynamics of Non-Crystalline Materials II

Chair: Yoichi Nakajima

21:20-21:50 Invited Talk
14:20‐14:50
Understanding diffraction patterns of glassy, liquid andamorphous materials via topological analyses

Yohei Onodera

21:50-22:10 Local structural investigation of non-crystalline
14:50‐15:10 materials at high pressure

22:10-22:30 The structure of bismuth oxide glasses
15:10‐15:30

RIL3

Kyoto University, Japan

Xinguo Hong

RO5

Center for High Pressure Scienceand Technology Advanced
Research, China
Katsuki Hayashi

RO6

Ehime University, Japan

22:30-22:40 Coffee Break
15:30‐15:40
22:40-23:40 Session R5
15:40‐16:10
Structure and Dynamics of Non-Crystalline Materials III

Chair: Yohei Onodera

22:40-23:00 Atomic structure of bulk metallic glasses studied by
15:40‐16:00 transmission electron microscopy, synchrotronradiation X-ray diffraction, scanning tunnelingmicroscopy and ab-initio molecular dynamics
simulation

Dmitri V. Louzguine

23:00-23:20 Short range order controlling the atomic dynamics in
16:00‐16:20 metallic glasses
23:20-23:40 On the relationship between structural state,
16:20‐16:40 mechanical properties and wear resistance of a cubased bulk metallic glass

RO7

National Institute of Advanced
Industrial Science and Technology(AIST), Japan
Xiao-Dong Wang

RO8

Zhejiang University, China
Paul Laffont

RO9

University Grenoble Alpes, SIMaP,
FranceOnline Conference Programme

JST
CEST

Day 5 - Friday 9th, September 2022

Chair: Satoshi Ohmura
16:00-17:15 Plenary Session / Session R6
9:00‐10:15
Phase Transitions and Thermophysical Behaviors I / State of the Art Manufacturing
16:00-16:40 Plenary Talk
9:00‐9:40
Behaviors of disordered alloys under high temperatureand pressure

Jian-Zhong Jiang

16:40-16:55 Corporate Webinar Talk
9:40‐9:55
Heraeus AMLOY Technologies – The transition fromscientific innovation to series production of highperformance application solutions

Hans-Jürgen Wachter

16:55-17:15 Large-scale density fluctuations during structural
9:55‐10:15 transition in metallic glass forming liquid beyond
medium range order

RPL1

Zhejiang University, China

RCW1

Global Head of Heraeus AMLOY,
Germany

Fan Yang

RO10

Institute of Materials Physics inSpace, Germany

17:15-17:25 Coffee Break
10:15‐10:25
17:25-18:20 Session R7
10:25‐11:20 Poster Short Presentation

Chair: Shuji Munejiri

18:20-19:00 Poster Session RPS1
11:20‐12:00
19:00-20:00 Meal Break
12:00‐13:00
20:00-21:00 Session R8
13:00‐14:00
Phase Transitions and Thermophysical Behaviors II

Chair: Makina Saito

20:00-20:20 Structure and dynamics in the no-man’s land of phase13:00‐13:20 change materials

Shuai Wei

20:20-20:40 Thermoplastic forming capacity of a ZrCoAl metallic
13:20‐13:40 glass for surface patterningLoïcia Gaudilliere

20:40-21:00 Shape memory effect in metallic glasses
13:40‐14:00

Tianding Xu

RO11Aarhus University, Denmark
RO12

University Grenoble Alpes, SIMaP,
FranceZhejiang University, China

RO13

Online Conference Programme
21:00-21:10 Coffee Break
14:00‐14:10
21:10-22:10 Session R9
14:10‐15:10 Phase Transitions and Thermophysical Behaviors III

Chair: Ayano Chiba

21:10-21:30 Role of Y content on glass-forming ability and soft
14:10‐14:30 magnetic properties of Co-Y-B metallic glasses

Shuang Ma

21:30-21:50 Formation of a local structural order in the aluminum
14:30‐14:50 melt before crystallization

21:50-22:10 Development of metal-metalloid high-entropy bulk
14:50‐15:10 metallic glasses with ultrahigh thermal stability andstrength

RO14

Dalian University of Technology,
China
Vadim B.Vorontsov

RO15

Ural State University of Railway
transport (USURT), Russia
Yanhui Li

RO16

Dalian University of Technology,
China

22:10-22:20 Coffee Break
15:10‐15:20
22:20-23:20 Session R10
15:20‐16:20
Phase Transitions and Dynamic Properties

Chair: Hironori Shimakura

Cancelled
22:20-22:40 Change of collective dynamics in supercooled glass15:20‐15:40 forming aluminium film
22:40-23:00 Atomic transport properties of Bi1-x Znx segregating
15:40‐16:00 alloys

RO17
Dmitrii Fleita

RO18

HSE University, Russia
G. M. Bhuiyan

RO19

University of Dhaka, Bangladesh

Online Conference Programme

JST
CEST

Day 6 - Monday 12th, September 2022

16:00-17:00 Session R11
9:00‐10:00
Machine Learning I

Chair: Kohei Shimamura

16:00-16:30 Invited Talk
9:00‐9:30
High-Dimensional Neural Network Potentials for
Simulations of Complex Systems

Jörg Behler

16:30-17:00 Invited Talk
9:30‐10:00
Structural inheritance and machine learning formaterials design: from study of liquid to prediction
crystals

RIL4

Universität Göttingen, Germany

Nikolay Chtchelkatchev

RIL5

Vereshchagin Institute for High
Pressure Physics, Russia

17:00-17:10 Coffee Break
10:00‐10:10
17:10-18:00 Session R12
10:10‐11:00
Poster Short Presentation

Chair: Shuta Tahara

18:00-18:40 Poster Session RPS2
11:00‐11:40
18:40-20:00 Meal Break
11:40‐13:00
20:00-20:50 Session R13
13:00‐13:50
Machine Learning II

Chair: Akihide Koura

20:00-20:30 Invited Talk
13:00‐13:30
Finite-temperature modeling of materials with firstprinciples accuracy

Michele Ceriotti

20:30-20:50 Composition Dependence of Melting Temperature of
13:30‐13:50 Rb-Na Alloy Using First-principles-based
Thermodynamic Integration

20:50-21:00 Coffee Break
13:50‐14:00

RIL6

École Polytechnique Fédérale deLausanne, Switzerland
Ayu Irie

RO20

Kumamoto University, Japan

Online Conference Programme

Chair: Osamu Yamamuro
21:00-22:00 Session R14
14:00‐15:00
Thermodynamics and Structure of Non-Crystalline Materials I
21:00-21:30 Invited Talk
14:00‐14:30
Response of the Free Energy Landscape toTemperature Modulation and Aging

21:30-22:00 Invited Talk
14:30‐15:00
New understanding of liquid thermodynamics, viscosity
and its lower bounds

Takashi Odagaki

RIL7

Kyushu University and ResearchInstitute for Science Education Inc.,Japan
Kostya Trachenko

RIL8

Queen Mary University of London,
United Kingdom

22:00-22:10 Coffee Break
15:00‐15:10
Chair: Yoshifumi Sakaguchi
22:10-23:00 Session R15
15:10‐16:00 Thermodynamics and Structure of Non-Crystalline Materials II
22:10-22:40 Invited Talk
15:10‐15:40 Thermodynamic and Structural Studies on Glass
Transitions of Molecular Glasses

Osamu Yamamuro

RIL9

The University of Tokyo, Japan

22:40-23:00 On the thermodynamics and its connection to structure Nico Neuber
RO21
15:40‐16:00 in the Pt-Pd-Cu-Ni-P bulk metallic glass forming system
Saarland University, Germany

23:00-23:10 Closing
16:00‐16:10

Organizers

Local Poster Programme

LAM-18 Conference
Local Poster Programme
Day 1 - Monday 5th, September 2022
15:50-17:50 Poster Session PS1

Day 2 - Tuesday 6th, September 2022
16:40-18:40 Poster Session PS2
P1

P2

P3

Determination of cooperatively rearranging regions inbinary glass former

Tomoko Mizuguchi

Novel Experimental Scheme for Microscopic Study ofJohari-Goldstein Process

Makina Saito

Kyoto Institute of Technology,
Japan

Tohoku University, Japan

Configurational entropy of an isotropic monatomic glass A. Ueno
Kyoto Institute of Technology,
Japan

P4

Anomaly of Linear Thermal Expansion Coefficientinduced by rejuvenation treatment

Tomoya Oshikiri
Hokkaido University, JapanP5

The structural analysis of low-density liquid phosphorus Takuya Nishioka
using reverse Monte Carlo simulation
Ehime University, Japan

P6

Local Structure of Ga85.8In14.2 eutectic liquid alloy andits pressure temperature melting line

Andrea Di Cicco

Development of an Analysis Method for Liquid
Electrolyte at a Lithium Electrode Interface using X-ray
Total Reflection

Koji Kimura

Structure of amorphous Mg85Zn6Y9 alloy as a seed of along-period stacking ordered structure

Shinya Hosokawa

Collective dynamics of liquid sulfur across thepolymerization transition temperature probed byinelastic x-ray scattering

Shinya Hosokawa

Phonon dynamics of liquid Hg probed by inelastic x-ray
scattering

Shinya Hosokawa

P7

P8

P9

P10

University of Camerino, Italy

Nagoya Institute of Technology,
Japan

Kumamoto University, Japan

Kumamoto University, Japan

Kumamoto University, Japan

Local Poster Programme

P11

P12

P13

P14

P15

P16

P17

P18

Inelastic x-ray scattering experiments for liquid
GeCu2Te3

Masanori Inui

Q-gap behavior of low energy excitations in liquid Sband liquid Bi observed by inelastic x-ray scattering
measurements

Masanori Inui

Phonon dispersion curves in the type-I crystalline andmolten clathrate compound Eu8Ga16Ge30

Masanori Inui

Density response function of valence electrons in liquidLi

Kazuhiro Matsuda

Relationship Between Liquid Dynamics and Potential
Energy Landscape

Noel Jakse

Selecting atomic fingerprints for high-dimensional
neural network potentials: adaptive group lasso
approach

Johannes Sandberg

GeO2 glass structure from neural network potential
molecular dynamics –dependence of intermediaterange order on density functional approximation

Kenta Matsutani

Optical properties of molten pure copper by density
functional theory

Susumu Kato

Hiroshima University, Japan

Hiroshima University, Japan

Hiroshima University, Japan

Kumamoto University, Japan

Université Grenoble Alpes, CNRS,FranceUniversité Grenoble Alpes, CNRS,FranceYamagata University, Japan

National Institute of Advanced
Industrial Scienceand Technology (AIST), Japan

Online Poster Programme

LAM-18 Conference
Online Poster Programme
JST
CEST

Day 5 - Friday 9th, September 2022

17:25-18:20
10:25‐11:20

Session R7

18:20-19:00
11:20‐12:00

Poster Session RPS1

Poster Short Presentation

Day 6 - Monday 12th, September 2022
17:10-18:00
10:10‐11:00

Session R12

18:00-18:40
11:00‐11:40

Poster Session RPS2

RP1

RP2

Poster Short Presentation

Development and optimization of sulfur-containing
novel Ti-based Bulk Metallic Glasses and thecorrelation between primary crystalline phases,
thermal stability and mechanical properties

Lucas Matthias Ruschel

Structural analysis of etidronate disodium

Hironori Shimakura

Saarland University, Germany

R7
RPS1
RPS2

R7

Niigata University of Pharmacy
RPS1
and Applied Life Sciences, Japan
RPS2

RP3

Topological analysis for α-AgI

Shuta Tahara
University of the Ryukyus, Japan

R7
RPS1
RPS2

RP4

RP5

Glass transition temperature of nickel based binary
alloys and its interparticle dynamics features

Local density fluctuation realized in Nb-Ni amorphousalloysDmitrii Fleita
Joint Institute for High
Temperatures of the Russian
Academy of Sciences, Russia
Toru Kawamata
Tohoku University, Japan

R7
RPS1
RPS2

R7
RPS1
RPS2

RP6

Unsupervised topological learning of crystal nucleationin pure metals

Sébastien Becker

RPS1

Université Grenoble-Alpes, France

R12
RPS2

Online Poster Programme

P1

P2

Determination of cooperatively rearranging regions inbinary glass former

Tomoko Mizuguchi

Novel Experimental Scheme for Microscopic Study ofJohari-Goldstein Process

Makina Saito

Kyoto Institute of Technology,
Japan

Tohoku University, Japan

R7
RPS1

R7
RPS1
RPS2

P5

The structural analysis of low-density liquid
phosphorus using reverse Monte Carlo simulation

Takuya Nishioka

RPS1

Ehime University, Japan

R12
RPS2

P7

P8

P9

P10

P11

Development of an Analysis Method for Liquid
Electrolyte at a Lithium Electrode Interface using X-ray
Total Reflection

Koji Kimura

Structure of amorphous Mg85Zn6Y9 alloy as a seed ofa long-period stacking ordered structure

Shinya Hosokawa

Collective dynamics of liquid sulfur across thepolymerization transition temperature probed byinelastic x-ray scattering

Shinya Hosokawa

Phonon dynamics of liquid Hg probed by inelastic xray scattering

Shinya Hosokawa
Kumamoto University, Japan

RPS1

Inelastic x-ray scattering experiments for liquid
GeCu2Te3

Masanori Inui

RPS1

Hiroshima University, Japan

R12

Nagoya Institute of Technology,
Japan

Kumamoto University, Japan

Kumamoto University, Japan

R7
RPS1

R7
RPS1

R7
RPS1

R7

RPS2
P12

P13

Q-gap behavior of low energy excitations in liquid Sband liquid Bi observed by inelastic x-ray scattering
measurements

Masanori Inui

RPS1

Hiroshima University, Japan

R12

Phonon dispersion curves in the type-I crystalline andmolten clathrate compound Eu8Ga16Ge30

Masanori Inui

RPS1

Hiroshima University, Japan

R12

RPS2

RPS2
P14

Density response function of valence electrons inliquid Li

Kazuhiro Matsuda

RPS1

Kumamoto University, Japan

R12
RPS2

Online Poster Programme

P15

P16

P17

P18

Relationship Between Liquid Dynamics and Potential
Energy Landscape

Noel Jakse

Selecting atomic fingerprints for high-dimensional
neural network potentials: adaptive group lasso
approach

Johannes Sandberg

RPS1

Université Grenoble Alpes, CNRS,FranceR12

GeO2 glass structure from neural network potential
molecular dynamics –dependence of intermediaterange order on density functional approximation

Kenta Matsutani

RPS1

Yamagata University, Japan

R12

Optical properties of molten pure copper by density
functional theory

Susumu Kato

RPS1

National Institute of Advanced
Industrial Scienceand Technology (AIST), Japan

R12

R12

Université Grenoble Alpes, CNRS, RPS2France

RPS2

RPS2

RPS2

Online Poster Short Presentation Programme

LAM-18 Conference
Online Poster Short Presentation Programme
JST
CEST

Day 5 - Friday 9th, September 2022

17:25-18:20 Session R7
10:25‐11:20
Poster Short Presentation
17:25-17:30 Development and optimization of sulfur-containing
10:25‐10:30 novel Ti-based Bulk Metallic Glasses and thecorrelation between primary crystalline phases, thermal
stability and mechanical properties

Lucas Matthias Ruschel

17:30-17:35 Structural analysis of etidronate disodium
10:30‐10:35

Hironori Shimakura

17:35-17:40 Topological analysis for α-AgI
10:35‐10:40

Shuta Tahara

17:40-17:45 Glass transition temperature of nickel based binary
10:40‐10:45 alloys and its interparticle dynamics features

Dmitrii Fleita

17:45-17:50 Local density fluctuation realized in Nb-Ni amorphous
10:45‐10:50 alloys

Toru Kawamata

17:50-17:55 Determination of cooperatively rearranging regions in
10:50‐10:55 binary glass former

Tomoko Mizuguchi

17:55-18:00 Novel Experimental Scheme for Microscopic Study of
10:55‐11:00 Johari-Goldstein Process

Makina Saito

18:00-18:05 Development of an Analysis Method for Liquid
11:00‐11:05 Electrolyte at a Lithium Electrode Interface using X-ray
Total Reflection

Koji Kimura

18:05-18:10 Structure of amorphous Mg85Zn6Y9 alloy as a seed of a
11:05‐11:10 long-period stacking ordered structure

Shinya Hosokawa

18:10-18:15 Collective dynamics of liquid sulfur across the
11:10‐11:15 polymerization transition temperature probed byinelastic x-ray scattering

RP1

Saarland University, Germany

RP2

Niigata University of Pharmacy andApplied Life Sciences, Japan
RP3

University of the Ryukyus, Japan
RP4

Joint Institute for High
Temperatures of the Russian
Academy of Sciences, Russia
RP5

Tohoku University, JapanP1

Kyoto Institute of Technology,
Japan
P2

Tohoku University, Japan
P7

Nagoya Institute of Technology,
Japan
P8

Kumamoto University, Japan
Shinya Hosokawa
Kumamoto University, JapanP9

Online Poster Short Presentation Programme

18:15-18:20 Phonon dynamics of liquid Hg probed by inelastic x-ray
11:15‐11:20 scattering

JST
CEST

Shinya Hosokawa

P10

Kumamoto University, JapanDay 6 - Monday 12th, September 2022

17:10-18:00 Session R12
10:10‐11:00
Poster Short Presentation
17:10-17:15 Unsupervised topological learning of crystal nucleation
10:10‐10:15 in pure metals

Sébastien Becker

RP6

Université Grenoble-Alpes, France

17:15-17:20 The structural analysis of low-density liquid phosphorus Takuya Nishioka
10:15‐10:20 using reverse Monte Carlo simulation
Ehime University, Japan

P5

17:20-17:25 Inelastic x-ray scattering experiments for liquid
10:20‐10:25 GeCu2Te3

P11

17:25-17:30 Q-gap behavior of low energy excitations in liquid Sb
10:25‐10:30 and liquid Bi observed by inelastic x-ray scattering
measurements

Masanori Inui
Hiroshima University, Japan
Masanori Inui
Hiroshima University, Japan

17:30-17:35 Phonon dispersion curves in the type-I crystalline and10:30‐10:35 molten clathrate compound Eu8Ga16Ge30

Masanori Inui

17:35-17:40 Density response function of valence electrons in liquid
10:35‐10:40 Li

Kazuhiro Matsuda

17:40-17:45 Relationship Between Liquid Dynamics and Potential
10:40‐10:45 Energy Landscape

Noel Jakse

17:45-17:50 Selecting atomic fingerprints for high-dimensional
10:45‐10:50 neural network potentials: adaptive group lasso
approach

Johannes Sandberg

17:50-17:55 GeO2 glass structure from neural network potential
10:50‐10:55 molecular dynamics –dependence of intermediaterange order on density functional approximation
17:55-18:00 Optical properties of molten pure copper by density
10:55‐11:00 functional theory

P12

P13

Hiroshima University, Japan
P14

Kumamoto University, Japan
P15

Université Grenoble Alpes, CNRS,France
P16

Université Grenoble Alpes, CNRS,FranceKenta Matsutani

P17

Yamagata University, Japan

Susumu Kato

P18

National Institute of Advanced
Industrial Scienceand Technology (AIST), Japan

Oral Presentations
Abstracts

PL1

Plenary

Mon. 5, Sep. 9:30-10:10

Medium-range Order and Cluster Connectivity
Si Lan1,2, Zhenduo Wu3,2, Xiaoya Wei2, *Xun-Li Wang2,41

Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of
Science and Technology, Nanjing 210094, China
2
Department of Physics, City University of Hong Kong, City, 83 Tat Chee Ave., Kowloon, Hong Kong
3
Center for Neutron Scattering and Applied Physics, City University of Hong Kong Dongguan ResearchInstitute, Dongguan 523000, China
4City University of Hong Kong Shenzhen Research Institute, Shenzhen Hi-Tech Industrial Park, Shenzhen
518057, China*
xlwang@cityu.edu.hk
Keywords (Maximum: 6 keywords, Minimum: 3 keywords, 10 point): Synchrotron scattering, neutron scattering,
short-range order, medium-range order, cluster, connectivity.
Amorphous materials have no long-range order, but there are ordered structures at short-range (2-5 Å),
medium-range (5-20 Å), and even longer-length scales [1,2]. While regular and semiregular polyhedra are often
identified as short-range ordering in amorphous materials, the nature of the medium-range order has remained
elusive. In a recent study of a Pd-Ni-P amorphous alloy during crystallization, we captured an intermediate
crystalline cubic phase and found a six-membered tricapped trigonal prism cluster (6M-TTP) existing in bothphases [3]. The 6M-TTP clusters can periodically pack to several tens of nanometers to form the cube phase. In
this regard, our experimental observations established a structural link between the amorphous and crystalline
phases and suggested that it is the connectivity of the 6M-TTP clusters that distinguish the crystalline andamorphous phases. Furthermore, we found the idea of cluster connectivity to be rather versatile, as it can explain
the structure evolution during crystallization [3,4], mechanical deformation [5], and liquid-to-liquid phasetransformation [6], where the short-range order structures or the clusters change only slightly. Rather, it is theconnectivity between clusters at a medium-range scale that drives the dynamic response. In this talk, we
discuss the meaning of cluster connectivity within the context of these in situ experimental results.
References.
1. D. B. Miracle, Nature Materials 3, 697-702 (2004).
2. D. Ma, A. D. Stoica, and X.-L. Wang, Nature Materials, 8, 30-34 (2009)
3. S. Lan et al., Nature Materials, 20, 1347–1352 (2021)
4. X.-L. Wang et al., Phys. Rev. Lett., 91, 265501 (2003).
5. D. Ma et al., Phys. Rev. Lett., 108, 085501 (2012)
6. S. Lan et al., Nature Comms., 8, 14679 (2017)

Fig. 1. A structure model illustrating the unit cell of the intermediate cubic crystalline phase in a
Pd-Ni-P metallic glass during crystallization. (a) Red balls are Pd and Ni atoms, whereas the blue balls
represent P atoms. The orange-colored polyhedron represents the Pd-enriched small cluster, and theblue-coloured polyhedron represents the Ni-enriched small cluster. Only part of the small clusters is
displayed for clarification. (b). Schematic diagrams showing the construction of the 6M-TTP clusterby the edge-sharing scheme. The 6M-TTP cluster is the structural link between the cubic crystalline
and the amorphous phases.

IL1

InvitedMon. 5, Sep. 10:10-10:40

The Intermediate-Range Structure of Glasses
as seen from their Magnetic Properties and Under an Optical Microscope*

Giancarlo Jug1,2,3

1

DiSAT, Università dell’Insubria, 22100 Como, 22100, Italy, 2INFN Sezione di Pavia, 27100 Pavia, Italy,
To.Sca.Lab Università dell’Insubria, 22100 Como, Italy*
giancarlo.jug@uninsubria.it
Keywords: Glass structure, SQUID-Magnetometry, Nanometric structures, Optical microscopy.
3

While the atomic-range- and long-range-structure of glasses are basically agreed upon, theintermediate-range has witnessed controversy since the early 1930s. In this talk I shall argue that
low-temperature experiments (particularly in a magnetic field) have recently contributed enormously to elucidate
such intermediate structure as being characterized by frozen-in heterogeneities that issue from the super-cooled
liquid state. When creating glass through avoided-crystallization, the liquid is characterized by solid-likefluctuations already in the proximity of Tx (the crystallization temperature). A highly correlated liquid ensues
upon rapid cooling and the seeding with solid-like particles creates growing quasi-ordered clusters (Regions ofEnhanced Regularity, RER) that jam-pack at the onset of glass formation. The RER become static and trap intheir “voids” particles that remain liquid-like all the way down to the lowest temperatures (T<<Tg , Tg thenominal “glass transition” temperature). These liquid-like regions are responsible for a plethora of new
phenomena known as cryogenic anomalies: I will show that the magnetic (and other) effects arise from somecollective yet localized modes and are responsible for new puzzling physical phenomena. I shall review the
most-probable explanation for the magnetic and other anomalies, including a rationale for the so-called
Two-Level Systems (TLS). The discovery of a new unexpected true magnetic effect will be reported andexplained in its unusual details in the light of a new microscopic theory that relies on the existence of collective
tunneling modes in the said “voids” between the RER. These collective modes have staggering new physics
properties. At the same time, the creation in the laboratory of a glassy multi-silicate specimen provides theconfirmation at milli-metric scale of the proposed cellular intermediate structure at the nano-metric scalecharacterizing all glasses. Including metallic glasses. Visible to the naked eye, and well-characterized in an
optical and better in a scanning electron-microscope, the cells remain non-crystalline though seeded by dirt andnano-crystals and provide for the solidity of the whole specimen. Images taken with a simple smartphone camera
and an optical microscope reveal a cellular, self-similar and fractal structure where the solid-like regions are
jam-packed and yet present no crystallinity. The two investigations (SQUID-magnetometry and purpose-seedingof the hot liquid) corroborate each other and give full support to the cellular model of glasses.

Left: temperature dependence of the intrinsic
magnetization of a borosilicate glass at 3.0(red) and 5.0 (black) Tesla. Beside theunexpected peak at low temperatures, clear
temperature oscillations arise at higher
temperatures.
Right: smartphone camera image of thecellular structure (whitish regions) in amacroscopic BaO-Al2O3-SiO2 glass specimen
seen from above (meniscus of the vitrified
liquid). Specimen diameter 16 mm.

O1

Mon. 5, Sep. 10:40-11:00

Structural Origin of Temperature Memory Effect of Quenched Strain in Metallic
Glasses*

Masato OHNUMA1, Pawel KOZIKOWSKI1, Giselher HERZER2, Ryuichi HASHIMOTO1,
Tomoya OSHIKIRI1, Merkus KUHNT2, Chrsitian POLAK2
1
Hokkaido University, Sapporo, Postal code060-8628, Japan, 2 Vacuumschmelze GmbH &Co.KG, Hanau, D63450, Germany*
ohnuma.masato@eng.hokudai.ac.jp
Keywords: Stress annealing, Linear Thermal Coeeficient, Localized flow unit

Stress annealing (SA) induced magnetic anisotropy is known in iron, nickel and cobalt-based ferromagnetic
metallic glass ribbons and it has already been used in commercial processes. Uniaxial elastic strain is introduced
by SA and is quenched into the ribbons even after cooling and removing the external stress. The release of theuniaxial quenched strains is clearly observed as an anomaly in the linear thermal expansion coefficient, LTEC,
when the ribbon is re-heated without stress as. The rate of strain release corresponding to the LTEC anomaly,
reaches a maximum at the temperature at which the original
SA was performed shown in Fig.1. We have observed thistemperature memory effect for the first time over the wholetemperature range from 280 to 400ºC, which is below thecrystallization temperature, Tx. As shown in Fig.2, theobserved results are explained well by the existence of a
localized “flow unit” embedded in an elastic matrix, which isaccepted as the origin of the shear band formation andrejuvenation of metallic glasses with Tg,(glass transition
temperature) < Tx. Although Tg is hardly visible in calorimetry
measurements in most of the ferromagnetic metallic glass
ribbons (Tg > Tx), the results here indicate that the same
important structural feature is common to metallic glasses withboth Tg < Tx and Tg > Tx. Because magnetization behavior isFig.11) Relation between SA temperatures and peakvery sensitive to the existence of residual elastic strain which
temperatures in LTEC. The difference in colors
correspond to two experiments with different atmosphereis difficult to evaluate in most of the metallic glasses, detailed(blue: in air, red: under N2 flow). The dotted line
studies, and a revival of interest in ferromagnetic ribbons willcorresponds to the case that peak temperature perfectly
help us to understand more about the nature of the localized
agree with the SA temperature.
flow unit, as well as non-affine deformations.

Fig.21) Models for the mechanism of the temperature memory effect. In (a) to (d), atoms inside the flow unit are shown in red andatoms in the elastic matrix are shown in blue. Dashed green lines are eye-guides for the elastic strain, i.e. the distance between #3
atoms and the line1-2 is perpendicular to the external stress. The atoms in blue can move only elastically through the SA, while theatoms in red have high mobility when ribbons are heated for SA. The dotted green curves show the original (before SA) shape of acage formed by the innermost atoms in the elastic matrix. The solid curve shows the elastically deformed cage produced by theexternal stress ((b) and (c)) or the accommodation of atoms inside the cage ((d)).

References (Example: non-mandatory, 10 point):
1) P.Kozikowski, M.Ohnuma, R.Hashimoto, K.Takano, G.Herzer, M.Kuhnt, C.Polak, Phys.Rev. Mater.,

4(2020), #095604

CL1

Committee

Mon. 5, Sep. 11:20-11:45

Synthesis and Mechanical Property of Highly Structure Controlled Metallic
Glasses by Thermal Rejuvenation Technique*

J. Saida1,#, W. Guo1,2, R. Yamada1,3, W.H. Ryu1,41

Frontier Research Institute for Interdisciplinary Sciences (FRIS), Tohoku University, 980-8578, Japan, 2 StateKey Lab of Materials Processing and Die & Mould Technology, Huazhong University of Science andTechnology, 430074, China, 3 Institute for Materials Research, Tohoku University, 980-8577, Japan, 4Department of Materials Science and Engineering, Research Institute of Advanced Materials & Institute ofEngineering Research, Seoul National University, Seoul 08826, Republic of Korea*
jsaida@fris.tohoku.ac.jp
Keywords: Metallic glass, Thermal rejuvenation, Relaxation, Mechanical property, Local structure
Metallic glasses have random atomic configuration intrinsically and generally exhibit attractive mechanicalbehaviors such as high strength, elastic modulus, hardness and wide elastic limit1. Recent progress of alloy
development for highly stabilized glassy structure (high glass-forming ability) has enabled us to produce glassy
alloys with a bulky shape. Such bulk metallic glasses (BMGs) are expected to apply for new industrial parts witha precision shape due to their attractive properties. Metallic glasses also cause a slight local atomic structurechange, that is, “structural relaxation” by low temperature annealing and/or mechanical processing, which
generally leads to serious embrittlement. However, since it has not been reported an effective way to get back theless relaxed state from the relaxed metallic glass, it has been necessary to avoid relaxation during a machining
process until now.
The authors have studied the relaxation behavior in metallic glasses under the cooling process from the melt.
Consequently, we have reported the strong dependence of relaxation state with the cooling rate just above theglass transition temperature, Tg in the supercooled liquid state2. The results indicate a possibility of recovering
the less relaxed metallic glass by a simple way using thermal process with heating above Tg for short duration
followed by a rapid cooling. Actually, we succeeded in preparation of the recovered less relaxed metallic glassfrom the relaxed one by appropriate annealing and cooling conditions in Zr-Al-(Ni)-Cu and Mg-Cu-Ag-Gd
BMGs3-8. This recovering process is so called as “rejuvenation”. These rejuvenated metallic glasses generally
bring a mechanical softening with improved ductility. It is due to the re-introduction of free volume and local
atomic structure change in the metallic glass4,5,9.
In this presentation, detailed rejuvenation process and improved mechanical properties in metallic glasses
will be reported. These studies provides beneficial information on the industrial application of metallic glasses.
References:
1. for example, A. Inoue, Acta Mater. 48, 279 (2000)
2. J. Saida et al., Met. Mater. Trans. 42A, 1450 (2011)
3. J. Saida et al., Appl. Phys. Lett. 103, 221910 (2013)
4. M. Wakeda et al, Sci. Rep. 5, 10545 (2015)
5. J. Saida et al., Sci. Tech. Adv. Mater. 18, 152 (2017)
6. W. Guo et al., J. Non-Cryst. Solids 498, 8 (2018)
7. W. Guo et al., Met. Mater. Trans. 50A, 1125 (2019)
8. W.H. Ryu et al., NPG Asia Mater. 12, 52 (2020)
9. M. Wakeda et al., Sci. Tech. Adv. Mater. 20, 632 (2019)

O2

Mon. 5, Sep. 11:45-12:05

High-entropy design and its influence on glass-forming ability
in Zr–Cu-based metallic glass*

Y. Ohashi1, T. Wada2, H. Kato2

1

Department of Materials Science, Graduate School of Engineering, Tohoku University, Sendai 980-8577, Japan,
Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan*
yusuke.ohashi.q4@dc.tohoku.ac.jp
Keywords: Bulk metallic glass, High-entropy alloy, Glass-forming ability.
2[Introduction] Bulk metallic glasses (BMGs) and high-entropy alloys (HEAs) are advanced materials that are
attracting much attention in both the industrial and academic fields because of their various properties that differ
from those of conventional alloys. BMGs have no long-range structural periodicity in their atomic arrangement
and are generally obtained from freezing a disordered liquid structure below the glass transition temperature (Tg).
HEAs are crystalline alloys with equimolar compositions of five or more elements, which form a single-phasesolid solution with a simple lattice. Four core effects have been proposed [1], and several HEAs with novel
properties that cannot be obtained with conventional materials have been reported. High-entropy metallic glasses,
which combine the properties of BMGs and HEAs, have high mixing entropy in the liquid phase, and theconfusion principle [2] is also applicable to them and excellent glass-forming ability is expected. BMGs haveenhanced GFA in eutectic compositions, but most HEBMGs are set to equimolar compositions for entropy
maximization, and alloys that combine both eutectic composition and high mixing entropy are currently
extremely limited. In this work, we systematically increased the number of components up to a senary systemand fabricated new Zr-Cu-based multicomponent eutectic alloys. By doing so, we attempted to clarify the effectof component increase to the high-entropy region on the GFA from the thermodynamic and kinetic viewpoints.
[Experiments] The alloys were prepared by arc-melting high-purity elements of Zr, Hf, Al, Ag, Cu, and Ni
under Ar gas. The fully melted alloy was poured into a cylindrical copper mold to produce rapidly quenched bulk
samples. Heat treatment was performed by sealing specimens in a quartz tube under a vacuum of less than 5 ×
10−3 Pa, and held at 1000 K, just below the melting point of the specimens, for 12 hours using an electric furnace.
The phase of the cast specimens was identified using X-ray diffractometers. The microstructure and compositionof the phase were analyzed by a scanning electron microscope equipped with an energy-dispersive spectrometer.
Thermal analyses were performed using a differential scanning calorimeter (DSC8500, PerkinElmer) to evaluate
the solidification behavior, phase transformation temperature and specific heat capacity.
[Results] Fig. 1 shows the slow-cooled solidification microstructure of the fabricated quaternary alloy,
confirming its eutectic composition. Increasing the number of components in Zr–Cu-based eutectic alloys, e.g.,
Zr48Al8Ag8Cu36 (n = 4, Dmax = 25 mm), and Zr35Hf13Al11Ag8Ni8Cu25 (n = 6, Dmax = 14), does not result inincreasing the GFA. A clear tendency exists where the GFA of the alloy decreases when the additive element issolidly dissolved into the original liquid competitive crystalline phase. This is because of the thermodynamical
stabilization of the dissolved crystalline phase from the increased configurational entropy, which results inincreasing the driving force of the eutectic reaction. In contrast, the GFA of the alloy increased when the additiveelement created a new crystalline phase. Ag and Ni have larger differences in atomic size and chemicalinteractions with other elements compared with the substitution source, Cu. The addition of Ag and Ni forms a
new phase, and thus enhances the GFA in a Zr–Cu-based eutectic alloy. However, Hf has a smaller difference inatomic size from the substitution source, Zr, and a smaller
heat of mixing difference from the constituent elements, so
the Hf additive tends to replace Zr sites in the original
crystalline phase, thus degrading the GFA. The GFA of theZr–Cu-based multicomponent eutectic alloys can beunderstood using both thermodynamic and kinetic parameters,e.g., the Zr48Al8Ag8Cu36 quaternary alloy with the largest
GFA bears both a smaller driving force for the eutectic
reaction and the smallest fragility parameter (m = 38). In
contrast, the Zr31.6Hf13.4Al8.7Ag8.4Cu37.8 quinary alloy with thesmallest GFA bears the largest driving force for the eutectic
reaction and the largest fragility parameter (m = 44).
References:1) M.H. Tsai et al., Mater. Res. Lett. 3 (2014) 107-123.
2) A.L. Greer, Nature. 366 (1993) 303.

Fig 1. Slow-cooled eutectic microstructure ofquaternary alloy

IL2

InvitedMon. 5, Sep. 14:00-14:30

Dynamic heterogeneities in undercooled metallic alloys*

Noel Jakse1

1

Université Grenoble-Alpes, CNRS, Grenoble INP, SIMaP, F-38000 Grenoble, France.
noel.jakse@grenoble-inp.fr
Keywords: Dynamic Heterogeneities, Ab initio simulation, Molecular dynamics, alloys, undercooling, Machinelearning.

*

Understanding evolution of dynamic properties in undercooled liquids and their interplay with their structuralfeatures represents an important issue for solidification processes of metallic alloys, such as crystallization andformation of quasi-crystalline or amorphous phases [1–4]. In the present work, we focus on various classes of
Aluminum alloys such as Al-Ni [5], Al-Cu [6], Al-Cr [7] and Al-Zn-Cr [8] that we investigated using ab initio
molecular dynamics. We simulate the undercooling process of these alloys during which we monitor the
structural and atomic transport properties. We find that diffusion, viscosity and structural relaxation time undergoa crossover between an Arrhenius and non-Arrhenius behavior at a temperature TX during the slowing down,
which corresponds to an onset of developing dynamic heterogeneities (DHs). The structural features display
characteristics compatible with the occurrence of the icosahedral short-range order (ISRO) as well as thedevelopment of a medium range order (MRO) upon cooling. The interplay between the ISRO, MRO and DHs isexamined. New developments in detecting such heterogeneities using unsupervised topological learning will be
discussed [9].
[1] C. P. Royall and S. R. Williams, Phys. Reports 56, 1 (2015).
[2] H. Tanaka, Eur. Phys. J. E 35, 113 (2012).
[3] Y. Q. Cheng and E. Ma, Prog. Mater. Sci. 56, 379 (2011).
[4] K. F. Kelton, G.W. Lee, A. K. Gangopadhyay, R.W. Hyers, T. J. Rathz, J. R. Rogers, M. B. Robinson, and D.
S. Robinson, Phys. Rev. Lett. 90, 195504 (2003).
[5] N. Jakse and A. Pasturel. J. Chem. Phys. 143, 084508 (2015).
[6] N. Jakse and A. Pasturel, AIP Adv. 7, 105212 (2017).
[7] N. Jakse and A. Pasturel, Phys. Rev. B 95, 144210 (2017).
[8] A. Pasturel and N. Jakse, npj Computational Materials 3, 33 (2017).
[9]S. Becker, E. Devijver, R. Molinier, and N. Jakse, Sci. Rep. (Nature) 12, 3195 (2022).

O3

Mon. 5, Sep. 14:30-14:50

Relaxation dynamics of glass forming metals: Study of aging, anelasticity andsupercooled liquid behavior in a ZrTiCuNiBe alloy*

E. Pineda1, M. Nabahat1

Department of Physics, Institute of Energy Technologies, Universitat Politècncia de Catalunya – BarcelonaTech,
Barcelona, 08019, Spain*
eloi.pineda@upc.edu
Keywords: Metallic glasses, physical aging, anelasticity, mechanical spectroscopy.
1

The structural relaxation of supercooled liquids (SCL) and glasses involves spatial and temporal
heterogeneity, a high degree of cooperativity and long timescales. The complex relaxation spectrum ofdisordered materials, the effects of aging and the wide range of experimental timescales make difficult to relate
the different observations in a whole picture of the liquid-glass dynamics. We will present here our recent workon a Zr46.75Ti8.25Cu7.5Ni10Be27.5 alloy. This glass forming alloy is characterized by an outstanding stability against
crystallization and decomposition. In addition, the mechanical spectrum shows a single α relaxation peak withno evidence of a secondary process. This makes this material a good model to get insight into the dynamics ofmetallic glasses discarding, as maximum as possible, the peculiarities of each particular composition.
Firstly, we will present the anelastic, or delayedelasticity, behavior. This phenomenon is particularly
large in glasses due to a broad distribution of reversible
deformation modes. Recovery experiments after
different loading times show that the time distribution ofmodes is invariant over a large range of temperatureswith a τ-n dependence, that can be directly related to thehigh-frequency wing of the α relaxation. Fig. 1 shows
the mechanical spectrum (a), the distribution ofrelaxation modes (b) and the corresponding anelastic
recovery functions (c). Secondly, we will show the stressrelaxation behavior obtained by strain step tests in boththe SCL and glass states1. In the SCL, the relaxation
functions show an invariant shape, fulfilling thetime-temperature superposition principle and inagreement with the viscosity behavior. In the glass state
the relaxation becomes stretched, indicating an increaseof dynamical heterogeneity. The study of the physicalaging process, performed by means of step strain tests
after different isothermal annealing times, shows that theatomic mobility decreases with an aging shift rate ofµ~0.5 and, interestingly, the dynamical heterogeneity
increases. This result implies that the dynamics becomes
more heterogeneous in more stable glassy states,
contrarily to the homogenization expected when thesystem evolves towards the equilibrated SCL
configuration. Thirdly, we will compare the mechanicalFig. 1. a) Mechanical spectrum of the ZrTiCuNiBe glass. b)
results with microscopic insights obtained by X-ray
Distribution of reversible relaxation modes generating the
Photon Correlation Spectroscopy. At temperatures neartransient creep and the recovery behaviors. The colored areas
indicate the fraction of modes activated after different loading
and above Tg, the mechanical and microscopic results
times c) Anelastic recovery functions after different loadingshow a constant dynamical heterogeneity, fulfilling thetimes. The shape of the function remains invariant and thetime-temperature superposition principle. Below Tg, thetimescale evolves linearly with loading time.
microscopic and macroscopic dynamics disagree in both
functional shape and timescale. The intermediate scattering function changes from a stretched shape in the SCL
to a compressed and fast decay in the glass. Taking into account the aging and anelasticity behaviors, this effectmay be explained by how the aging rate and the stress relaxation are observed in the microscopic scale. Finally,
we will summarize the complete view of the metallic glass relaxation dynamics and we will compare with theresults observed in other glass forming alloys.
References:
1) N. Amini, Phys. Rev. Mater. 5, 055601 (2021).

O4

Mon. 5, Sep. 14:50-15:10

Emergent structural heterogeneity and it’s effect on viscosity and transport
in a model binary metallic glass*

P. M. Derlet1, H. Bocquet1, R. Maass2,31

Condensed Matter Theory Group, Paul Scherrer Institut, Forschungsstrasse 111, 5232 Villigen PSI, Switzerland
Federal Institute of Materials Research and Testing (BAM), Unter den Eichen 87, Berlin 12205, Germany
3
Department of Materials Science and Engineering, University of Illinois at Urbana Champaign, 1304 West
Green Street, Urbana, IL 61801, USA*
peter.derlet@psi.ch
Keywords: Metallic glasses, Atomistic simulation, Structural heterogeneity, Structural evolution, Deformation2

How thermally activated structural excitations quantitatively mediate transport and micro-plasticity in amodel binary glass at the micro-second time-scale is revealed using atomistic simulation. It is found that such
local excitations underlie the transport of free volume and bond geometry. Viscosity estimates are obtained
giving a relaxation time-scale that is comparable to the strain recovery timescales seen in micro-plasticity
simulations. The transport is found to correspond to the evolution of a disclination network describing the spatialconnectivity of topologically distinct bonding environments, demonstrating the important role of geometricalfrustration in both glass structure and its underlying thermally activated dynamics. The character of thisdisclination network, and how it emerges from quenching of the under-cooled liquid, is studied revealing asystem-spanning micro-structure of icosahedral and Frank-Kasper structural motives which are essentiallyfrozen at the time scale of molecular dynamics. Upon loading in the nominally elastic deformation regime, thisleads to a dissipation-driven heterogeneous internal stress distribution, and upon unloading negative creep andcomplete residual-strain recovery.
References:
1) P. M. Derlet, H. Bocquet, and R. Maass, Phys. Rev Mater 5, 125601 (2021).
2) P. M. Derlet and R. Maass, Acta. Mater. 209, 116771 (2021).
3) P. M. Derlet, Phys. Rev. Mater. 4, 125601 (2020).

O5

Mon. 5, Sep. 15:10-15:30

Creation of Three-Dimensional Relaxation State Gradient in Zr50Cu40Al10
Metallic Glass Through a Thermal Process*

Rui Yamada1,3, Wook Ha Ryu2, Haruka Isano3, Tomohiro Yoshikawa3, Junji Saida3

1

Institute for Materials Research, Tohoku University, Sendai, 980-8577, Japan, 2 Research Institute of Advanced
Materials & Institute of Engineering Research, Seoul National University, Seoul, 08826, Republic of Korea, 3
Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, 980-8578, Japan.
*
rui.yamada.b6@tohoku.ac.jp
Keywords: metallic glass, relaxation state gradient, thermal process
Metallic glasses are attracted much attention in engineering materials owing to their superior mechanicalproperties and formability, which are originated from a unique random atomic configuration (amorphous
structure). Previous studies revealed that the amorphous structure is not completely random but it would berather heterogeneous1). Recently, manipulation of heterogeneity through tailoring a relaxation state is intensively
studied with the aim of extending the range of a glassy state2). One of the representative processes is mechanicalway such as cold rolling, shot peening, high pressure torsion (HPT) etc.2). These processes are based on a heavy
plastic deformation with introducing gigantic strain in the sample. Though such processes achieved a certain
success in tailoring a glassy state, there still have some drawbacks. One is that these processes inevitably
destruct an initial geometry shape of a sample. Another problem is that some of the process does affect only on asurface but it is difficult on a whole area. The third is that applicable sample size is limited, accordingly, most ofthem can apply only for a bulk sample. From these backgrounds, it has been highly desired a new process tosolve these problems.
A thermal process is one of the strong candidates for meeting such demands. It is realized that, unlike themechanical way, the process is non-destructive and there is no shape change. In addition, it is isotropic,
homogeneous, and it can affect not just a part but an entire area of the sample. Moreover, it can apply to any
shape of samples like ribbon, disk, bulk etc.. Because of these advantages, thermal process is currently getting
attention regarding on tailoring the relaxation state heterogeneity.
In our previous study, it was revealed that a glassy state can be tuned by changing a cooling rate from asupercooled liquid region3). It was also found from a dynamic mechanical analysis that heterogeneities of thesamples are different from each other with cooling rate3). These results confirmed that a relaxation state
heterogeneity can be tailored through the thermal process. More recently, our research group revealed that
relaxation state gradient can be created in a single monolithic metallic glass with creating a cooling rate
difference within a rod sample4). Interestingly, the sample with relaxation state gradient showed an improved
ductility during compression.
Though a creation of the gradient has already attained for a simple case (i.e. two-dimensional), more complex
case (e.g. three-dimensional) has never been achieved yet. Moreover, key factors for creating such relaxation
state gradient through the thermal process are still uncertain. Therefore, the objectives of the present study are tocreate a three-dimensional relaxation state gradient in a Zr50Cu40Al10 metallic glass through the thermal process
and to clarify what factors do affect a creation of the gradient.
In the present study, a sample holder with a tilt angle of 24 degree against a horizontal direction is newly
developed aiming to create the relaxation state gradient in the diagonal direction of the rod sample. Zr50Cu40Al10
rod sample was firstly heated to a supercooled liquid region and then one side of the holder was cooled down
rapidly by attaching a Cu mesh which was indirectly cooled with liquid nitrogen in advance. After the heat
treatment, a specific heat measurement and an indentation test were conducted to evaluate the creation ofrelaxation state gradient.
It was revealed that three-dimensional relaxation state gradient was successfully created in the rod sample
through the thermal process. Thermal conductivity of the as-cast sample was calculated to be around 5-18
W/m・K which is far below the normal pure metal data. From the result, it was suggested that this low thermal
conductivity of the sample plays an important role in a creation of relaxation state gradient during the heat
treatment. Our present findings will give a beneficial information for creating a relaxation state heterogeneity inmetallic glasses.
References:
1) H. B. Yu et al., National Science Review 1, 2014, 429-461.
2) Y. Sun et al., Nature Reviews Materials 1, 2016, 1-14.
3) J. Saida et al., Science and Technology of Advanced Materials 18, 2017, 152-162.
4) W.H. Ryu et al., NPG Asia Materials, 2020, 12:52.
#
Present address: Institute for Materials Research (IMR), Tohoku University, Sendai, 980-8577, Japan.

PL2

Plenary

Tue. 6, Sep. 9:20-10:00

How the Liquid Structure is Formed; Bottom-up, Top-down, or Both?
*

T. Egami1,2

1

Shull-Wollan Center, University of Tennessee, Knoxville, TN 37996, USA, 2 Oak Ridge National Laboratory,
Oak Ridge, TN 37831, USA*egami@utk.edu
Keywords: Liquid structure, Medium-range order, Pseudopotential, Density wave.
Liquid is a condensed matter of which physical density is similar to that of solid. Atoms form a random
structure with short- and medium-range atomic correlations. To elucidate such local correlations has long been amajor challenge. The conventional approach is to start with local structural units made of several atoms, and touse them as building blocks to form a global structure, the local bottom-up approach. However, this approach
fails to explain the strong drive to form the medium-range order (MRO) which is different from the short-rangeorder (SRO) in nature [1,2]. We propose to add an alternative global top-down approach to explain the driving
force to form the MRO. In this approach we start with a high-temperature gas state and then apply interatomic
potentials to all atoms at once. This causes collective density wave instability in all directions with the same
wavelength. These two driving forces, local and global, are in competition and are mutually frustrated. The final
structure is determined through the compromise of frustration between these two, which creates the MRO. Thiseven-handed approach on global and local potential energy landscapes explains the distinct natures of SRO and
MRO, and strong temperature dependence of various properties of liquid.
The key to the top-down approach is the use of the pseudopotential. To consider all atoms at once it is moreconvenient to use reciprocal space. However, the Fourier-transform of the interatomic potential, (r), is
dominated by the strongly repulsive part of the potential and is meaningless. We consider the pseudopotential bytruncating (r) at a cut-off distance, rc, to remove the diverging repulsive part of the potential, and assume pp(r)= (rc) for r < rc [1]. This is reasonable because at short distances no pair of atoms are found, so that the strongly
repulsive part of the potential has no physical effect on the liquid. The Fourier-transform of pp(r) has a strong
minimum at q1 which only weakly depends on rc as shown in Fig. 1.
The minimum in pp(r) at q1 causes density waves with q (q = q1) for all directions, forming a Bragg sphere.
This state is the structurally coherent ideal glass state, conceived in extrapolation from the real liquid state [4].
The pair-distribution function (PDF), g(r), of liquid and glass decays with distance as g(r)-1 ~ exp(-r/)/r, assuggested by Ornstein and Zernike. Thus, the PDF of the ideal state is obtained as g0(r) = g(r)exp(r/). This state
has long-range density correlations and is described by the density wave model. The local structure of this stateis very diverse, with little icosahedral order [4]. Therefore, this state is not compatible with the driving force toform the SRO. This conflict between the SRO to minimize the local energy and the density wave to minimize theglobal energy is resolved by the compromise, resulting in the MRO. Thus, the structural coherence length of
MRO, , reflects the balance. When the density wave is strong  is long, whereas it is short when the SRO
dominates. Therefore, it is short for systems with strong covalent bonds, and long for systems with metallic
bonds. For this reason, the MRO coherence length is directly related to liquid fragility [5] through  ~ m3, wherem is the fragility coefficient [6]. Furthermore, the activation energy for viscosity is proportional to the coherence
volume, 3, suggesting that the resistance by thedensity wave, not structural defects, determines
the mechanical properties. Thus, the density wave
theory explains a wide range of liquid properties.
References:
1) C. W. Ryu and T. Egami, Phys. Rev. E 104,
064109 (2021).
2) T. Egami and C. W. Ryu, Phys. Rev. E 104,
064110 (2021).
3) T. Egami and C. W. Ryu, Frontier Mater., inpress (2022).
4) C. W. Ryu, W. Dmowski, K. F. Kelton, G. W.
Lee, E. S. Park, J. R. Morris and T. Egami, Sci.
Rep. 9, 18579 (2019).
5) C. A. Angell, Science 267, 1924 (1995).
6) C. W. Ryu and T. Egami, Phys. Rev. E 102,042615 (2020).

Fig. 1 The Fourier-transform of the pseudopotential for the Johnson
potential for Fe, with various cutoff energies. The energy minimum
causes the density waves.

IL3

InvitedTue. 6, Sep. :0-10:0

Hydrodynamic Interaction Between Quasi-elastic and Acoustic Modes
Observed by Inelastic X-Ray Scattering
Alfred Q.R. Baron and Daisuke Ishikawa
baron@spring8.or.jp
Materials Dynamics Laboratory, RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, JAPAN
Precision Spectroscopy Division, CSRR, SPring-8/JASRI, Sayo, Hyogo, 679-5198, JAPAN
Keywords: Mesoscale Liquid Dynamics, Dynamic Structure Factor, Water, Inelastic X-Ray Scattering

Improvements in methodology and instrumentation for meV-resolved inelastic x-ray scattering(IXS) [1–4], coupled with a fresh examination of older theory (e.g. [5]), allow identification of aninteraction between the quasi-elastic and acoustic phonon modes in liquids [6]. This helps
explain a decades old controversy about the appearance of additional modes in water spectra,
and provides a strong base to discuss new phenomena in liquids on the mesoscale. Further, we findthat the intensity of the quasi-elastic peak in water is in good quantitative agreement with an estimate
from a simple viscoelastic model [7] using the magnitude of the positive dispersion, so the hugeincrease in the quasi-elastic scattering in water on the mesoscale (relative to the long wavelength
Landau-Placzek ratio) can robustly be interpreted as being due to the relaxation that causes fastsound [6]. We also show that including the interaction changes the fit results, resulting in significant
changes to the observed sound velocity relative to a model without interaction.
[1]A. Q. R. Baron, in Synch. Light Srcs. & FELS, edited by E. Jaeschke, et al.(Springer International Publishing, Cham,
2016), pp. 1643-1757. See also arXiv 1504.01098. [2] D. Ishikawa, D. S. Ellis, H. Uchiyama, and A. Q. R. Baron, J.
Synch. Rad. 22, 3 (2015). [3] A. Q. R. Baron, D. Ishikawa, H. Fukui, and Y. Nakajima, AIP Conf. Proc. 2054, 20002(2019). [4] D. Ishikawa and A. Q. R. Baron, J. Synch. Rad. 28, 804 (2021). [5] J. P. Boon and S. Yip, Molecular
Hydrodynamics (Dover Publications, Mineola, New York, 1980). [6] D. Ishikawa and A. Q. R. Baron, J. Phys. Soc. Japan
90, 83602 (2021). [7] R. D. Mountain, J. Res. Natl. Bur. Stand. -A. Phys. Chem. 70A, 207 (1966).

IXS from water at 301K at Q=2.5 nm-1. The various contributions are as indicated. A fit
with the full interacting model (black line) gives small residuals (reduced chi-squared
0.92, probability>0.5) while a fit without interaction gives large and correlated residuals(reduced chi-squared 1.56, probability<10-5). [6]O6Tue. 6, Sep. :30-10:50

Ab initio Study of Collective Excitations in Liquid Sb
Taras Bryk1,2, *Ari Paavo Seitsonen3
1

Institute for Condensed Matter Physics of NASU, UA-79011 Lviv, Ukraine, 2 Lviv Polytechnic National
University, UA-79013 Lviv, Ukraine, 3 Département de Chimie, École Normale Supérieure, F-75005 Paris,
France*Ari.P.Seitsonen@iki.fi
Keywords: collective excitations, speed of sound, generalized hydrodynamics, ab initio computer simulations

We report ab initio and machine learning study of dynamic properties of liquid Sb at temperature 973 K. The
thermodynamic point corresponds to a recent experimental study of collective dynamics in liquid Sb by inelastic
X-ray scattering [1]. In the ab initio simulation we used a system of 600 particles in order to reach small wave
numbers k for the density-density and current-current time correlation functions. Additionally we used the
trajectories, the forces on the ions and the total energies as input quantities in machine learning for fitting a
potential for liquid Sb. We were able to perfectly recover structural properties of liquid Sb by machine learning
as well as reasonable agreement for single-particle dynamic quantities.
The spectra of collective excitations in liquid Sb from ab initio simulations were derived by two
methodologies: one was purely numerical via peak positions of longitudinal and transverse current spectral
functions, while the second was based on an advanced approach of generalized eigenmode analysis of timecorrelation functions proposed for the case of ab initio simulations in Ref [2]. We discuss the comparison ofsimulation and experimental dynamic structure factor S(k,ω) and collective modes contributing to it in different
regions of the (k,ω)-plane. Additionally we report an analysis of positive dispersion for longitudinal collective
excitations outside the hydrodynamic region.

References:1) M. INUI et al, J. Phys.: Condens. Matt. 33, p 475101 (2021)
2) T. BRYK and G. RUOCCO, Mol. Phys. 111, p 3457 (2013).

CL2

Committee

Tue. 6, Sep. 11:10-11:35

Interpretion of thermodynamic anomalies of liquid waterin terms of critical fluctuations*

Yukio Kajihara1, Kazuhiro Matsuda2

1

Hiroshima University, Higashi-Hiroshima, Hiroshima 732-8651, Japan, 2 Kumamoto University, Kumamoto
860-8555, Japan, *kajihara@hiroshima-u.ac.jp
Keywords: Liquid water, Thermodynamics, Liquid-liquid phase transition, Critical fluctuation
Liquid water near ambient conditions is known to exhibit various thermodynamic anomalies, and therelationship with the liquid-liquid phase transition (LLT), which is believed to exist in the supercooled region,
has been discussed [1]. However, the actual first-order (discontinuous) phase transition is proposed to exist in theextremely supercooled and high-pressure region (no-man’s land), and no conclusive experimental evidence has
yet been obtained to complete the debate.
On the other hand, thermodynamic anomalies similar to those of liquid water have been known for liquid Te,
and there is a long history of ongoing debate on the relationship with LLT separately from liquid water [2]. We
aim to gain a comprehensive understanding of the thermodynamic anomalies commonly seen in liquid water andliquid Te, focusing on critical fluctuations. The important point here is to discuss the critical fluctuations of the
LLT and liquid-gas phase transition (LGT), sorting out the similarities and differences. In LGT, density
inhomogeneity, as measured by small-angle scattering, is a key parameter for critical fluctuation. On the other
hand, in LLT, this density inhomogeneity = static critical fluctuation is overwhelmingly smaller than in LGT, afact that is not a quantitatively important parameter [3]; dynamic critical fluctuation is considered important in
LLT. As a physical quantity corresponding to this dynamic critical fluctuation, we have proposed the relaxation
intensity [3], which is obtained by measuring the frequency dependence of the sound velocity [3].
The presentation will discuss the effect of static and dynamic critical fluctuations of LLT and LGT on thethermodynamic quantities of liquid water, showing the temperature and pressure dependence of some important
thermodynamic quantities [4] (isochoric specific heat Cv is shown in the figure as an example).
.
References:
1) review: P. Gallo et al., Chem. Rev. 116, 7463 (2016)
2) Y. Kajihara et al., submitted; arXiv:2201.10065
3) Y. Kajihara et al., submitted; arXiv:2111.06589
4) W. Wagner et al., J. Chem. Ref. Data 31, 387 (2002)

Fig. 1. Pressure and temperature dependence of isochoric specific heat capacity of liquid water [4]O7

Tue. 6, Sep. 11:35-11:55

Phase relation between supercooled liquid and amorphous Silicon*

Junpei T. Okada1, Patrick H.-L. Sit 2, Takehiko Ishikawa3,4, Jinfan Chen2, Y. Watanabe5, P.-F.
Paradis3, Kaoru Kimura6, and Satoshi Uda1
1

Institute of Materials Research, Tohoku University, Sendai, Miyagi 980-8577, Japan, 2 School of Energy andEnvironment, City University of Hong Kong Kowloon, Hong Kong S. A. R, 3Institute of Space and Astronautical
Science, Japan Aerospace Exploration Agency (JAXA), Tsukuba, Ibaraki 305-8505, Japan, 4The Graduate
University for Advanced Studies (SOKENDAI), Sagamihara, Kanagawa 252-5210, Japan, 5Advanced
Engineering Services Co., Ltd. Tsukuba, Ibaraki 305-0032, Japan, 6Department of Advanced Materials Science,
The University of Tokyo, Kashiwa, Chiba 277-8561, Japan.
*

junpei.okada.b6@tohoku.ac.jp
Keywords: first order phase transition, supercooled liquid Si, amorphous Si, electrostatic levitation technique

It is well known that liquid Si (l-Si) can be deeply supercooled by preventing heterogeneous nucleation. The
phase relation between supercooled l-Si and amorphous Si (a-Si) has been widely investigated1-4). It should benoticed that the electronic properties and the atomic structures are different in l-Si and a-Si; the former ismetallic with the coordination number of 6 and the latter is semiconducting with the coordination number of 4.
Therefore, it is difficult for the supercooled l-Si to directly transform into a-Si. In our experiments,
electrostatically levitated l-Si samples were supercooled down to low temperatures, 300 K below the melting
temperature (Tcl: 1683 K) and solidified accompanied with the release of latent heat. It was found that solidified
Si samples melted again at 1480 K caused by the latent heat. Also, it was found that the Si samples rapidly
quenched near the solidification temperature contained a large amount of a-Si with the tetrahedral coordination.
These two findings indicate that the supercooled l-Si samples solidified into a-Si and a-Si melted, indicating afirst-order phase transition between two metastable phases5).

References
1) Y. Shao, F. Spaepen, and D. Turnbull, Metallurgical and Materials Transactions a-Physical Metallurgy andMaterials Science 29 (7), 1825 (1998).
2) A. Hedler, S. L. Klaumunzer, and W. Wesch, Nat. Mater. 3 (11), 804 (2004).
3) S. K. Deb, M. Wilding, M. Somayazulu, and P.-F. McMillan, Nature 414 (6863), 528 (2001)
4) T. Morishita, Phys. Rev. Lett. 93 (5), 055503 (2004).
5) J. T. Okada, P. H.-L. Sit, et al., Appl. Phys. Lett. 116, 093705 (2020).

IL4

InvitedTue. 6, Sep. 14:00-14:30

Structure of amorphous Cu-Ge-Te and the implications for its functionality*

J. R. Stellhorn1, S. Hosokawa2, B. Paulus3, B. D. Klee3, W.-C. Pilgrim3, N. Boudet4,
N. Blanc4, H. Ikemoto5, S. Kohara6 and Y. Sutou7
1
Hiroshima University, Higashi-Hiroshima 739-8527, Japan, 2 Institute of Industrial Nanomaterials, Kumamoto
University, Kumamoto 860-8555, Japan, 3 Philipps University of Marburg, 35032 Marburg, Germany, 4
Université Grenoble Alpes, CNRS, Institut Néel, 38000 Grenoble, France, 5 University of Toyama, Toyama
930‐8555, Japan, 6 National Institute for Materials Science, Hyogo 679-5148, Japan,7 Tohoku University, Sendai
980-8579, Japan*stellhoj@hiroshima-u.ac.jp
Keywords: phase-change material, amorphous local structure, anomalous X-ray scattering, EXAFS

We have investigated the structure of amorphous Cu-Ge-Te (CGT) by a combination of anomalous X-ray
scattering (AXS) and extended X-ray absorption fine-structure (EXAFS) experiments [1,2]. In particular,
Cu2GeTe3 is a novel phase-change material (PCM), i.e. it exhibits a reversible change from an amorphous phase
to a crystalline phase, which can be utilized to encode binary data. CGT is expected to be used for a next
generation of (nonvolatile) data storage devices due to its favorable properties [3,4]. For example, the CGT
crystalline film was found to be amorphized by laser irradiation with a lower power and shorter pulse width thancurrently employed and widely studied Ge-Sb-Te alloys, which are essential properties to achieve rapid data
recording and low power consumption in PCMs [3-5]. Further differences between these PCM systems are areverse density change, i.e. amorphous CGT is actually denser than the crystal, and a negative optical contrast,
i.e. the reflectivity of the crystalline phase is lower than that of the amorphous phase, contrary to Ge-Sb-Te [6].
The experimental AXS and EXAFS data are analyzed with reverse Monte Carlo (RMC) modeling, and they
are interpreted in terms of short-range-order parameters as well as by using ring statistics and persistenthomology to study the intermediate-range order. Based on this information, the structural relationship of theamorphous phase to the corresponding crystal can be discussed. It is found that the amorphous network can berationalized by small atomic displacements of the crystal structure, directed toward the intrinsic void regions.
This structural similarity establishes the possibility of a fast phase-change process. On the other hand, the atomic
rearrangements also lead to the formation of new chemical bonds and to distortions on theintermediate-range-order level. These are realized by a collapse and contraction of the strict hexagonal ringarrangements of the crystal and by the formation of small, triangular rings as well as Cu cluster configurations.
These structural features allow for a new understanding of the phase-change property contrast of this material,
especially concerning the density change and the optical contrast.

Fig. 1. a) experimental AXS and EXAFS datasets (symbols) and results of the RMC modelling (colored lines).
b) model of the phase change-process regarding the ring structure.
References[1] J. R. Stellhorn et al, Phys. Rev. B. 101, 214110 (2020)[2] B. Paulus, J. R. Stellhorn, B. D. Klee, S. Hosokawa, W.-C. Pilgrim, Phys. Status Solidi B 2100619 (2022).
[3] Y. Sutou, T. Kamada, M. Sumiya, Y. Saito, and J. Koike, Acta Mater. 60, 872 (2012).
[4] Y. Saito, Y. Sutou, and J. Koike, Appl. Phys. Lett. 102, 051910 (2013).
[5] M. Wuttig and N. Yamada, Nat. Mater. 6, 824 (2007).
[6] N. Yamada, E. Ohno, K. Nishiuchi, N. Akahira, and M. Takao, J. Appl. Phys. 69, 2849 (1991).

CL3

Committee

Tue. 6, Sep. 14:30-14:55

X-ray and neutron diffraction ofsemi-crystalline isotactic poly (4-methyl-1-pentene) with alkane absorption*

Ayano Chiba1, Hiromi Murashige1, Yusuke Sanada2, Yusuke Hiejima3

1

Department of Physics, Keio University, Yokohama 223-8522, Japan, 2 Department of Chemistry, Faculty of
Science, Fukuoka University, Fukuoka, 814-0180, Japan, 3 Department of Chemical and Materials Science,
Kanazawa University, Kanazawa 920-1192, Japan*ayano@phys.keio.ac.jp
Keywords: X-ray diffraction, X-ray small-angle diffraction, Infrared absorption spectroscopy, Semi-crystalline
polymers, Polymer host-guest structures, Small-angle neutron scattering
We are studying the possibility that confined space is useful for liquid separation. Syndiotactic polystyrene(SPS) is known to form host-guest co-crystals with various small molecules, and it may be useful for liquid
separation because some small molecules are preferentially absorbed when an SPS film is immersed in a mixed
liquid [1,2]. Although there are many studies on SPS, there had been no study on isotactic poly
(4-methyl-1-pentene) (P4MP1) from such a point of view.
We used to study the structure of high temperature and high pressure liquids such as arsenic and antimony,and noticed that some similarities between the pressure-temperature (P-T) phase diagram of SPS and that of
P4MP1. Based on the similarity, it was conceived that the phenomena found in SPS might also occur in P4MP1.
With this idea, it was found that P4MP1 as-cast film absorbs various organic solvents [3]. Not only that, but
we also found the preferential absorption of long alkanes from a liquid mixture of long and short alkanes byusing this polymer film and it may be useful for liquid separation [3]. However, not even whether the solvent isabsorbed in the crystalline region or in the amorphous region is clear. We thus aimed to clarify the host-guest
structure when this polymer (host) absorbs small molecules such as alkanes (guests).
Generally, polymer semi-crystals have both crystalline and amorphous regions. The solvent is likely to beabsorbed in the amorphous region, which usually have lower density than crystalline regions. However, thedensity of the crystalline region of P4MP1 is slightly smaller than the density of the amorphous region, and there
was a possibility that it was absorbed in the crystalline region. In order to clarify whether the absorption was
mainly in the crystalline region or the amorphous region, samples with different crystallinities were prepared andthe solvent absorption was investigatedby infrared absorption spectroscopy. As
a result, it was found that more solvent
was absorbed in the amorphous region.
Specifically,
P4MP1
films
of
crystallinity of 38% and 26% absorbed
decane for 0.5 mmol/cm3 and 1.6
mmol/cm3, respectively.
We also measured small-angle
X-ray
scattering(SAXS)
accompanying absorption of thesolvent, and found that a peak occurred
at 0.15 nm-1 accompanying absorption.
This peak is assigned to the lamellar
long period, and is usually not observedin this polymer because the crystal andamorphous densities are too close. It
seems that the scattering contrast
became non-negligible as the solvent ispreferentiallyabsorbedintheamorphous region, and the peak
appears as the solvent is absorbed (Fig.
1). In the presentation, we will discuss
the results of wide angle x-ray Fig. 1. SAXS profile of the As-cast film (black thin line) and the time dependence ofdiffraction and small-angle neutron the profile of the film after hexane is added. Orange dashed line, red thick line, andblack dotted line show the SAXS profile of the as-cast film at 30, 360 and 1200 s after
scattering as well.
hexane is added.
References:1) G. Guerra, C. Daniel, P. Rizzo, O. Tarallo, J. Polym. Sci. Part B: Polym. Phys. 50, 305 (2012).
2) Y. Uda, F. Kaneko, T. Kawaguchi, Macromol. Rapid Commun. 25, 1900 (2004).
3) A. Chiba, A. Oshima, R. Akiyama, Langmuir 35, 17177 (2019).

O9

Tue. 6, Sep. 14:55-15:15

Direct observation of concentration fluctuations in Au-Si eutectic liquidby small-angle neutron scattering*

Yoshifumi Sakaguchi1, Shin’ichi Takata2, Yukinobu Kawakita2

1

Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society(CROSS), Tokai, 319-1106, Japan, 2 J-PARC Center, Japan Atomic Energy Agency, Tokai, 319-1195, Japan*y_sakaguchi@cross.or.jp (Corresponding author)
Keywords: Eutectic alloys, melting point depression, small-angle neutron scattering.
Eutectic alloys have attracted much attention because of their low melting temperatures from both
application and scientific points of view. Especially, gold-silicon (Au-Si) alloy exhibits anomalous melting point
depression, which is more than 1000 ℃ from the melting point of pure Si (1414 ℃). It is noted that the eutectic
alloy is not a compound with lower melting point, but a mixture with two phases, Au and Si phases which havehigher melting points. According to the thermodynamics theory, the mixture melts at lower temperature than themelting points of individual elements when the free energy of the homogeneous liquid (completely mixed liquid)
is lower than the sum of the free energies of the two elemental solids. For Au-Si eutectic alloys, this mixing state
was proved by the detection of the Au-Si pair correlations from the diffraction measurements [1, 2] and themolecular-dynamics simulations [3-5]. However, it is not fully explained yet why the mixing occurs at such
lower temperatures at the specific eutectic composition (Au81.4Si18.6).
To date, an anomalous behavior in the deep eutectic liquids was pointed out from the electrical resistivity
measurements by Itami et al. [6]. They observed a deviation from a linear temperature dependence of theelectrical resistivity in liquid Ag-Si and Au-Si alloys and proposed that there were concentration fluctuations in
the liquids. A presence of concentration fluctuations contradicts the theoretical understanding of the eutectic
liquids where atoms are homogeneously mixed. However, such micro-heterogeneity in eutectic melts was also
pointed out by other research group [7] in the same period (2004), when the 12th International Conference on
Liquid and Amorphous Metals was held at Metz in France. Concentration fluctuations are often referred while
fluids above a critical point of two liquid phase separation are concerned. However, there may exist small
fluctuations of mixing state, where a clear liquid phase separation is not related. Assuming such concentration
fluctuations, they can disturb the solidification where each kind of atoms is perfectly aligned, resulting in theanomalous melting point depression.
To directly observe such concentration fluctuations in the Au-Si eutectic liquid, we performed small-angle
neutron scattering (SANS) measurement of Au81.4Si18.6 (room temperature ~ 800 ℃) and Au75Si25 (roomtemperature ~ 900 ℃) on BL15 (TAIKAN) at the Materials and Life Science Experimental Facility, Japan
Proton Accelerator Research Complex (J-PARC). To observe small SANS signals as clear as possible, wedeveloped a furnace for SANS measurement with a low background [8]. At room temperature, a large
small-angle scattering resulted from a sharp interface between Au and Si phases was observed in both samples.
In both liquids, there still remains a small-angle scattering although its intensity is weaker than that at room
temperature. This small-angle scattering in the liquid state could indicate a presence of concentration fluctuationsin the liquid which Itami et al. suggested. The relationship between the small-angle scattering and the anomalous
melting point depression is discussed in terms of the concentration fluctuations.
References:
1) H. Fujii, S. Tahara, Y. Kato, S. Kohara, M. Itou, Y. Kawakita, S. Takeda, J. Non-Cryst. Solids 353, 2094
(2007).
2) P. Chirawatkul, A. Zeidler, P. S. Salmon, S. Takeda, Y. Kawakita, T. Usuki, H. E. Fischer, Phys. Rev. B 83,
014203 (2011).
3) A. Pasturel, E. S. Tasci, M. H. F. Sluiter, N. Jakse, Phys. Rev. B 81, 140202(R) (2010).
4) N. Jakse, T. L. T. Nguyen, A. Pasturel, J. Phys.: Condens. Matter 23, 404205 (2011).
5) N. Jakse, T. L. T. Nguyen, A. Pasturel, J. Chem. Phys. 137, 204504 (2012).
6) T. Itami, H. Aoki, T. Shibata, M. Ikeda, K. Hotozuka, J. Non-Cryst. Solids 353, 3011 (2007).
7) P. S. Popel, M. Calvo-Dahlborg, U. Dahlborg, J. Non-Cryst. Solids 353, 3243 (2007).
8) Y. Sakaguchi, S. Takata, H. Arima, R. Takahashi, J. Neutron Res. 21, 29 (2019).

CL4

Committee

Tue. 6, Sep. 15:35-16:00

Structural Relaxation in Complex Liquid Metals, Antimony and Bismuth, by
Means of Coherent Quasi-Elastic Neutron Scattering and Time -Space
Correlation Function*

Y. Kawakita1, T. Kikuchi1,2,3, Y. Sakaguchi4, T. Hanashima4, R. Takahashi1, D. Wakai5, K.
Nakajima1
1

J-PARC Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki, 319-1195, Japan, 2 Sumitomo Rubber
industries, Ltd., 3-6-9 Wakinohama-cho, Chuo-ku, Kobe, Hyogo, 651-0072, Japan, 3 Institute of Materials
Structure Science, High Energy Accelerator Research Organization, Tokai, Naka, Ibaraki, 319-1106, Japan, 4
Neutron Science and Technology Center, Comprehensive Research Organization for Science and Society, Tokai,
Naka, Ibaraki, 319-1106, Japan, 5 NAT Corporation, Tokai, Naka, Ibaraki, 319-1112. Japan, Affiliation, City,
Postal code, Country (10 point)*
yukinobu.kawakita@j-parc.jp
Keywords Neutron scattering, Liquid metal, QENS, Time space correlation function, Antimony, Bismuth
Antimony (Sb) and bismuth (Bi) have A7 crystal structure which a simple cubic lattice is deformed to byPeierls distortion and is characterized as three short bonds and three long bonds1). The complex local structuresin their liquid state are considered to be originated from the Peierls distortion and inferred to have a layered
structure2). We performed quasi-elastic neutron scattering (QENS) by utilizing AMATERAS spectrometer3)
which is cold neutron disk chopper instrument installed at Materials and Life Science Experiment Facility(MLF) in Japan Proton Accelerator Research Complex (J-PARC) aiming at extraction of a direct evidence forlayered structure by difference in structural relaxation time between intra- and inter-layers. From QENS
experiments for Bi and Sb, their coherent dynamics structure factor is obtained directly because of small
incoherency of their neutron scattering
lengths, which is useful to deduce atime-space correlation function (tscf),
so-called van Hove function4).
Figure shows the tscf obtained for liquid
Sb at 650ºC. The top line exhibits the tscf at
t = 0,01 ps which is almost similar to paircorrelation function. It has a main peak
about at 3 Å accompanying shoulder andsmall peaks in a longer side up to about 4.6
Å. A time-evolution shows different
relaxation time among characteristic peaks.
The main peak has a relaxation time ofaround 0.3 ps which is contrast with much
longer relaxation of the main peak (theshortest bond) in liquid Bi. In thepresentation, we will discuss on structural Fig. 1. Time evolution of time-space correlation functions of liquid Sb at 650ºC.
with equi-interval in a logarithmic scale of time from 0.01 to 17.8 ps
anomaly in complex liquid metals from the 14 functionsare
shown with gradual shift from the top to the bottom..
viewpoint of structural relaxation dynamics
with comparing liquid Bi and Sb.
References:
1) R.W.G. Wyckoff, Crystal Structures, Wiley, New York, 1963.
2) M. Mayo, E. Yahel, Y. Greenberg, G. Makov, J. Phys. Condens. Matter 25 (2013) 505102 and so on.
3) K. Nakajima et al., J. Phys. Soc. Jpn. 80 (2011), SB028.
4) T. Kikuchi and Y. Kawakita; Physica B 567 (2019) 51.

O10

Tue. 6, Sep. 16:00-16:20

Estimating Thermal Conductivity of Silver Chalcogenides
Using Machine-Learning Interatomic Potentials*

K. Shimamura1, A. Koura1, F. Shimojo1

Department of Physics of Kumamoto University, Kumamoto, 860-8555, Japan
shimamura@kumamoto-u.ac.jp
Keywords: Green-Kubo method, Machine learning, Thermal conductivity, Silver chalcogenides.

1*

The Green-Kubo (GK) method, which is the combination of Molecular dynamics (MD) simulations and the
GK formula for estimating thermal conductivity (TC), have the powerful advantage of being applicable to evenirregular systems such as liquid systems. The combination of machine-learning interatomic potentials (MLIPs)
with the GK method further improves the accuracy of TC and broadens the scope of application. MLIPs, which
are trained with data from first-principles molecular dynamics (FPMD) simulations, successfully reproduce thehigh accuracy of FPMD while maintaining the low computational cost of conventional empirical interatomic
potentials (EIPs). The MD simulations using MLIPs can yield sufficient statistics concerning fundamental physicalquantities such as TC and free energy, or to investigate atomic dynamics in large-scale systems. However, eventhough heat flux is a major factor in the accuracy of TC in the GK method, the definitions of heat flux formulasfor MLIPs employed in the previous studies were inconsistent with each other. MLIPs is a many-body potentialthat includes not only two-body functions but also three-body functions, and heat fluxes that did not account forthe many-body effect have been used in previous studies. The heat flux formulas correspond to analogues of therigorous one for two-body interatomic potentials, which would fail to estimate TC. This meant that themethodology for the combination of MLIPs and the GK method had not yet been established.
Therefore, we aimed to establish a methodology that can calculate TC with high accuracy [1-3]. Here, artificial
neural networks were used for MLIPs (hereinafter referred to as ANN potential). The derivation of the heat flux
formula (referred to as 𝐉𝐉𝑸𝑸1 ) considering the many-body effect of ANN potentials was based on the previous work
for Tersoff-potential by Fan et al [4]. We also found that this 𝐉𝐉𝑸𝑸1 was closely related to the pressure formula of thevirial theorem. Current standard training of MLIPs does not guarantee pressure accuracy, which could interferewith accurate estimates of TC. It became necessary to train MLIPs with pressure. To investigate the effect of heat
flux formula 𝐉𝐉𝑸𝑸1 and pressure training on TC, we set a superionic conductor, α-Ag2Se, as the test system. The EIPof Ag2Se [5] was used to generate training data for ANN potentials. With EIPs, which have a low computationalcost, a reference TC value can be obtained in advance and compared with the TCs obtained from ANN potentials.
Figure 1 shows the absolute differences between the TC (κEP, 0.274 Wm-1K-1) obtained by the EIP of Ag2Se andthose obtained by ANN potentials (κANN) as function of pressure training errors (ΔP). Model 1 and Model 2 denote
the ANN potentials without/with pressure training, respectively. For comparison, the TCs calculated by the heat
flux formulas without considering the many-body effect (𝐉𝐉𝑸𝑸2 and 𝐉𝐉𝑸𝑸3 ) which were used in previous studies. In
addition, to clarify the dependence of the initial weight values ofANNs, we constructed five ANN potentials for each Model andcalculated κANN. Only when 𝐉𝐉𝑸𝑸1 and Model 2 were used, the absolutedifferences showed almost zero, indicating that κEP was reproduced
correctly. In contrast, Model 1, not only with 𝐉𝐉𝑸𝑸2 and 𝐉𝐉𝑸𝑸3 but also
even with 𝐉𝐉𝑸𝑸1 did not show the correct TC, and there were some ANN
potentials that showed significant deviation from κEP. This is due tothe fact that Model 1 does not guarantee pressure accuracy, and thedeviation was positively correlated with ΔP. Therefore, the use ofpressure training and the heat flux formula considering many-bodyeffect of MLIPs would be essential for TC calculations.
In the presentation, we will report the results using the above
method to compare the TCs obtained for not only the superionic
conducting phase but also liquid and low-temperature (β) phases ofsilver chalcogenides including Ag2Se.
Figure 1: The absolute differences between κEP
References:[1] K. Shimamura et al., J. Chem. Phys. 153, 234301 (2021).
[2] K. Shimamura et al., Chem. Phys. Lett. 778, 138748 (2021).
[3] Y. Takeshita et al., J. Phys. Chem. Solids 163, 110580 (2022).
[4] Z. Fan et al., Phys. Rev. B 92, 094301 (2015).
[5] J. P. Rino et al., J. Chem. Phys. 89, 7542 (1988).

obtained from the EIP for α-Ag2Se at 500 K andthe respective κANN calculated from ANN
potentials with five different initial weightvalues belonging to Model 1 or Model 2 as afunction of the training error (root mean squareerror, ΔP) [2]. κANN was calculated for each𝟏𝟏𝟐𝟐𝟑𝟑
Model using 𝐉𝐉𝑸𝑸
, 𝐉𝐉𝑸𝑸, and 𝐉𝐉𝑸𝑸
, respectively.

PL3

Plenary

Wed. 7, Sep. 9:20-10:00

Supercritical Elasticity and Structural Entanglement of Multicomponent alloys
Haiyang Chen1, Yan-Dong Wang1,*, Yang Ren2,*
1

Beijing Advanced Innovation Center for Materials Genome Engineering, State Key Laboratory for Advanced
Metals and Materials, University of Science and Technology Beijing, Beijing, China; 2 Department of Physics,
City University of Hong Kong, Kowloon, Hong Kong, China*
ydwang@mail.neu.edu.cn; yangren@cityu.edu.hk
Keywords: Supercritical elasticity, order and disorder entanglement, multicomponent alloys, X-ray/Neutron
scattering, Phase transformation.
Elasticity is an important property of solids. The elastic strain limit of metals rarely exceeds 1%. Shapememory alloys exhibit a large recoverable pseudo-elastic strain of up to 10% resulted from the stress-induced
martensitic transformation (SIMT). However, the intrinsic hysteresis and temperature sensitivity of thefirst-order phase transformation significantly hinder the usage of smart metallic components in many criticalareas, such as in deep-space and deep-sea exploration and intelligent robotics etc. We have prepared a series ofmetallic fibers of multicomponent alloys, Ni55-xCoxFe18Ga27, by the Taylor liquid drawing technique. We foundthat at low Co concentration, x=6, the fiber shows a stress-strain behavior with typical SIMT characteristics,
exhibiting a large hysteresis between the loading and unloading plateaus. With increasing Co concentration, theflat and hysteretic region diminishes, and trilinear non-hysteretic stress-strain responses occur. This peculiar
elastic behavior closely resembles the characteristicfeature of the isothermal pressure-volume (P-V)
curves of a gas-liquid system, where thediscontinuous P-V curve gradually becomescontinuous above a critical temperature/pressure.
Both pressure-volume and stress-strain curves present
energy variation of the system, reflecting
compressibility and elasticity, respectively. A
modified Landau model was proposed to describe thesupercritical feature of observed stress-strain curves,which indicate that an endpoint exist for the SIMT ata critical Co content. We found that fibers with highCo content exhibit over 15% non-hysteretic elasticity,a small temperature dependence, high-energy-storage
capacity and ultra-stable cyclability. In-situ
synchrotron X-ray diffraction measurements showthat the supercritical elasticity is correlated with astress-induced continuous variation of lattice
parameters accompanied by structural fluctuation.
Neutron diffraction and electron microscopy
observations reveals an unprecedented microstructure
consisting of atomic-level entanglement of ordered
and disordered crystal structures, which can be
manipulated to tune the supercritical elasticity. The
discovery of the large elasticity related to theentangled structure paves the way for exploiting Fig. 1. Super-elastic behavior and in situ synchrotron x-ray
elastic strain engineering and development of related diffraction of Ni55-xCoxFe18Ga27 single crystal fibers. (a) Stress–strain
curves for different Co-concentration alloys on loading andfunctional materials.
unloading. Inset: high resolution transmission electron microscope
References (Example: non-mandatory, 10 point):
1) H.Y. Chen, H., Wang, YD., Nie, Z. et al.
Unprecedented non-hysteretic superelasticity of[001]-oriented NiCoFeGa single crystals. Nat. Mater.
19, 712–718 (2020).

image of a Co20 alloy, showing an atomic-level entanglement ofordered/disordered structures. (b) Ultimate mechanical tests for the
Co20 alloy. (c) Cyclic stress–strain curves of the Co20 alloy
performed up to 8,000 cycles, without any degradation of thefunctional properties. (d) 2D neutron diffraction pattern collected at
298 K. (e) 1D neutron diffraction profiles of the characteristic region
delineated by the frame in d. (f) Lattice parameters a, b and c andd-spacing of (444) reflection as a function of engineering strain,
showing continuous changes.

CL5Committee

Wed. 7, Sep. 10:00-10:30

Investigation of local structural changes in GeSe2 glass under ultra-high pressure
Yimin Mijiti1, Joao Elias Rodrigues2, Aangela Trapananti1, Javad Rezvani1, Toru Shinmei3,
Tetsuo Irifune3, Angelika dorothea Rosa2, Andrea Di Cicco1,*
1School of Science and Technology, University of Camerino, Via Madonna delle Carceri 9, Camerino, MC
62032, Italy
2
European Synchrotron Radiation Facility - 71, avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9,France3
Geodynamics Research Center Ehime University Matsuyama 790-8577, Japan*andrea.dicicco@unicam.it
Keywords : EXAFS, Local structure, ultra-high pressure, chalcogenide glasses.
Experimental studies of ultra-high pressure (P>1 Mbar) polyamorphism in the covalently bonded network
forming amorphous systems has long been a challenging topic. There is not yet enough experimental data forconvincingly describe the densification and evolution of local structures in the common simple amorphousmaterials including SiO2 and other geophysically relevant disordered systems under ultra-high pressures (e.g,conditions in the deep Earth), because of the experimental challenges related with the studies of tiny amorphous
samples (typically in diamond anvil cells) using diffraction techniques. Here, using extended x-ray absorption
fine structure (EXAFS, an ideal probe of local structures in the amorphous systems) technique, we investigatedthe pressure induced local structural changes in the network forming GeSe2 glass under ultra-high pressuresexceeding 150 GPa. For each pressure point, EXAFS data have been measured scanning through both Ge and Se
K-edges along the same compression run, allowing us to perform more reliable data analysis using the doubleedge EXAFS refinements.

CL6

Committee

Wed. 7, Sep. 10:30-10:55

Bonding and structure of liquid iron-light-element-oxygen ternary alloys underhigh pressure: molecular dynamics simulations*

Satoshi Ohmura1, #, Fuyuki Shimojo2, Taku Tsuchiya3

1

Faculty of Engineering, Hiroshima Institute of Technology, Hiroshima, 731-5193, Japan,
Department of Physics, Kumamoto University, Kumamoto, 860-8555, Japan,
3
Geodynamics Research Center, Ehime University, Matsuyama, 790-8577, Japan.
*s.ohmura.m4@cc.it-hiroshima.ac.jp
Keywords: Liquid Fe ternary mixture, High-pressure, bonding property, Ab initio simulation.
2

Liquid iron-light-element (LE) mixture is a constituent of Earth’s outer core1[1.2]. LE have a strong
influence on the structural and transport properties of liquid iron under high pressure. However, there are still
many uncertainties regarding the influence of LE. Recently, a systematic theoretical investigation based on abinitio MD simulations for the LE-effect on the structural properties of liquid Fe–LE binary systems under highpressure was reported [3]. The simulation clarified that H, C, and O are incorporated into liquid Fe interstitially,
while Si and S are “substitutional” type impurities.
For the liquid Fe-LE-O ternary systems, several experimental and theoretical studies on the properties ofliquid Fe-LE-O, including immiscibility of liquid Fe-Si-O [4,5], have been reported. However, the detailed local
structures and bonding properties in liquid Fe–LE–O ternary systems, which are the origins of various propertiesof liquid, remain unclear. For this reason, in this study, we have investigated the structural and bonding
properties of liquid Fe-LE-O ternary systems such as Fe-H-O, Fe-C-O, Fe-Si-O and Fe-S-O under high pressureusing ab initio molecular-dynamics simulations.
From our simulations, it is found that H, C and O show “interstitial-type” behavior while Si and S show
“substitutional” type properties in the liquid iron-light-element-O ternary systems, similar to liquid Fe–LE binary
systems. For the interactions between light elements, C-C, Si-Si and Si-O shows covalent-like interactions while
H-H, S-S, C-O and S-O have no strong interactions. We will also discuss the effects of the covalent-likeinteractions on the atomic charges in the liquids.

Partial pair distribution functions of liquids Fe-H-O, Fe-C-O, Fe-Si-O and Fe-S-O at 140 GPa and 5000 K. (Bottom panel) Snapshots of
C-C bond in liquid Fe-C-O and Si-O bond in liquid Fe-Si-O

References (Example: non-mandatory, 10 point):
1) F. Birch, J. Geophys. Res. 69, 4377-4388 (1964)
2) J.-P. Poirier, Phys. Earth and Planet. Inter. 85, 319 (1994).
3) S. Ohmura, T. Tsuchiya and F. Shimojo, physica status solidi (b) 257, 2000098 (2020).
4) S.M. Arveson, et. al., Proc. Nat. Acad. Sci. 116, 10238 (2019).
5) D. Huang, et al., Geophys. Res. Lett. 46, 6397-6405 (2019)..

O11

Wed. 7, Sep. 10:55-11:15

Inelastic X-ray scattering measurements of liquid Fe-S at high pressure*

Yoichi Nakajima1,2, Asaki Iwamoto1, Yuki UENO1, Yasuhiro KUWAYAMA3,
Kei HIROSE3,4, Guillaume MORARD5, Daisuke ISHIKAWA2,6, Alfred Q.R. BARON2,6

1
Department of Physics, Kumamoto University, Kumamoto-shi, Kumamoto 860-8555, Japan, 2Material Dynamics
Laboratory, RIKEN Spring-8 Center, Sayo-cho, Hyogo 679-5148, Japan, 3Department of Earth and Planetary
Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan, 4Earth-Life Science Institute, Tokyo
Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan, 5 Université Grenoble Alpes, Université Savoie Mont
Blanc, CNRS, IRD, Université Gustave-Eiffel, ISTerre, 38000 Grenoble, France, 6JASRI, Sayo-cho, Hyogo 6795198, Japan*
yoichi@kumaoto-u.ac.jp
Keywords: Geoscience, Liquid alloys, Sound velocity, High-pressure, Inelastic X-ray scattering.

The physical properties of liquid Fe alloys are crucial to understanding planetary metallic cores. Terrestrial planets
such as Earth, Mercury, and Mars have molten cores. Because these cores are located inside deep planets, thepressure (P) and temperature (T) conditions are extremely high, e.g., the P-T conditions of Earth’s core are 136364 GPa and 4000-6000 K. Iron is the dominant component of planetary cores. The cores also contain lighter
elements such as H, C, O, S, and Si [1]. Longitudinal sound velocity (P-wave velocity) and density are the primaryobservables of Earth’s liquid core. Therefore, these properties of liquid Fe alloys under relevant extreme conditions
are important to investigate the core. Sulfur (S) is one of the candidates for the core light elements. Iron sulfides
are commonly found in variety of meteorites, and the S concentrations are relatively high in chondrites [2].
However, sulfur is depleted in Earth’s silicate mantle [3]. A recent study on the element partitioning between
magma ocean and core-forming metal proposed that a large amount of S could have been trapped in the coreforming metals during planetary formation processes [4]. To examine the possibility of S in the core, we havedetermined the P-wave velocity of liquid Fe-S alloy based on inelastic X-ray scattering (IXS) measurements.
We carried out IXS measurements at the RIKEN Quantum NanoDynamics beamline BL43LXU of SPring-8[5,6]. High P-T conditions were generated using a laser-heated diamond anvil cell. A foil of Fe83S17 was loaded in
LH-DAC together with single-crystal Al2O3 discs that act as thermal and chemical insulators. The sample melting
was confirmed based on X-ray diffraction measurements. IXS spectra of the liquids were collected in an energy
range of ±40 meV and a momentum transfer range of 3-5.7 nm-1 with an energy resolution of ~2.8 meV at 17.79
keV. Then we obtained the dispersion relation of the longitudinal acoustic phonon mode of the liquid sample. We
determined the P-wave velocity of liquid Fe83S17 at 32-98 GPa and 2100-2950 K from the dispersion relations
obtained at each P-T condition.
The P-wave velocity of liquid Fe83S17 is slightly higher than that of liquid Fe [7]. Using the present P-wave
data-set, we constructed an equation of state (EoS) for liquid Fe83S17 and estimated the P-wave velocity and density
under the core P-T conditions. Comparing with seismological observations of the outer core, we found liquid Fe
alloying with 6-7 wt% S to satisfy both P-wave velocity and density of the outer core simultaneously, which issimilar to the S content based on previous element-partitioning experiments [4]. The present results imply that S
can be the dominant light element in the Earth’s outer core.
References:
1) Stevenson, Science 214, 611-619 (1981).
2) Wasson and Kallemeyn, Phil. Trans. R. Soc. Lond. A 325, 535-544 (1988).
3) McDonough. Treatise on Geochemistry (Second Edition), 3, 559–577 (2014).
4) Mahan et al. Geohim. Cosmochim. Ata 196, 252-270 (2017).
5) Baron, SPring-8 Inf. Newsl. 15, 14-19 (2010).
6) Baron, in Synchrotron Light Sources and Free-Electron Lasers: Accelerator Physics, Instrumentation andScience Applications, edited by E. J. Jaeschke, S. Khan, J. R. Schneider, and J. B. Hastings (Springer, New York,
2016), pp. 1643–1757.
7) Kuwayama et al. Phys. Rev. Lett. 124(16), 165701 (2020).

CL7Committee

Wed. 7, Sep. 11:35-12:05

Simulation study of the collective excitations in liquid sodium under highpressure*

J.-F. Wax1, E. Mocchetti1,2

1

LCP-A2MC, Université de Lorraine, Metz, 57000, France,
CRM2, Université de Lorraine, Nancy, 54000, France.
*
jean-francois.wax@univ-lorraine.fr
Keywords: Molecular dynamics, dynamic structure, High pressure, sodium2

The dynamic structure of liquid sodium is investigated using classical molecular dynamics simulations over awide range of densities (from 951 to 4177 kg/m3) (see figure 1). The interactions are described using screened
pseudopotential formalism with Fiolhais model of electron-ion interaction. The effective pair potentials obtained
are validated by comparing the predicted static structure and self-diffusion coefficients with ab-initio simulations
at the same state point.
Both longitudinal and transverse collective excitations are computed from the corresponding current
correlation functions and their evolution with density is investigated. The frequency of the longitudinal
excitations increases with density (see figure 2), as well as the sound speed, which is extracted from theirdispersion curves. The frequency of the transverse excitations also increases with density, but they cannot
propagate over macroscopic distances and the propagation gap clearly appears (see figure 3). The value of theviscosity, which is extracted from these transverse functions is in good agreement with available results
computed from stress autocorrelation functions.

Fig. 1. Phase diagram of sodium and investigated state points.

Fig. 2. Longitudinal excitations dispersion curves.

Fig. 3. Transverse excitations dispersion curves.

O12

Wed. 7, Sep. 12:05-12:25

Structure of liquid Cd under high-pressure condition
F. Iesari1,*, T. Okajima1, M. Minicucci2, A. Trapananti2, A. Di Cicco2
1

Aichi Synchrotron Radiation Center, Seto, Aichi, 489-0965, Japan, 2 Physics Division, School of Science andTechnology, Camerino University, Camerino, 62032, Italy*fabio.iesari@aichisr.jp
Keywords: X-ray absorption, Reverse Monte Carlo, High-pressure, Ab-initio simulation
The structure of liquid metals lacks the long-range order typical of crystals, but still maintains a short-rangeordering. In particular, in previous studies the presence of local icosahedral configuration has been identified inliquid Cu and Ni [1,2], possibly explaining the deep undercooling properties of small metal particles. Under highpressure condition, molecular dynamics (MD) simulations have shown that the fraction of icosahedral ordering
increases in liquid Cu [3], at the expenses of crystal-like configurations (fcc, hcp).
In this work, we present a study on the structure of liquid cadmium under pressure probed both by experimental
X-ray absorption spectroscopy (XAFS) data [4] and computer simulations. Cd, like other group 12 elements,
possesses particular physical properties respect to other transition metals, like lower melting point, due to thecompletely filled d-orbital in the outer shell. At ambient condition, Cd crystallizes in an hexagonal structure, butwith an axial ratio c/a of ~1.886, far from the ideal value for hexagonal close-packed configuration, indicatingcomplex interactions that could also affect the liquid structure.
XAFS experiments have been carried out at different temperatures and pressures above the melting line: data
have been analyzed using the Reverse Monte Carlo (RMC) method to obtain compatible three-dimensional models,
which can be directly compared with ab-initio MD simulations. The evolution of the local structure at different
thermodynamic conditions is presented.

0.02
l-Cd T=350◦C

Expt.
RMC

6

12

χ(k)

0.01
0
−0.01
4

8
10
−1
k [Å ]

14

Fig. 1. EXAFS signal for liquid Cd at 350°C and ambient pressure and corresponding RMC fit.

References:
1) A. Di Cicco, A. Trapananti, S. Faggioni, and A. Filipponi, Phys. Rev. Lett. 91, 135505 (2003).
2) A. Di Cicco, F. Iesari, S. De Panfilis, M. Celino, S. Giusepponi and A. Filipponi, Phys. Rev. B 89, 060102(2014).
3) M. Celino, F. Coppati and A. Di Cicco, Solid State Sciences 12, 179-182 (2010).
4) M. Minicucci, A. Trapananti, A. Di Cicco, S. De Panfilis and G. Aquilanti, Physica Scripta T115, 1056-1058(2005).

O13

Wed. 7, Sep. 12:25-12:45

Ab initio simulation for the ductility mechanism of silver chalcogenides
H.Hokyo1, M. Misawa2, K. Shimamura1, A. Koura1, F. Shimojo1*
1

Kumamoto University, Kumamoto City, 860-8555, Japan, 2 Okayama University, Okayama City, 700-8530, Japan,
hokyohinata@gmail.com
Keywords : Silver chalcogenides, Ductilily, Ab initio simulation*

Silver chalcogenides are candidate for thermoelectric materials and attracting attention as new device materials.
Among them, Ag ! S is an important inorganic semiconductor that has metal-like ductility despite being asemiconductor [1]. On the other hand, Ag ! Se, which has a similar chemical composition, is non-flexible but has
high electrical conductivity suitable for thermoelectric materials. Experimental studies have reported that theductility is confirmed in the compositions Ag ! S"#$ Se$ (𝑥 ≤ 0.6) with Ag ! S-type (monoclinic) crystal structure[2]. In this study, we performed simple shear deformation simulations as shown in Fig. 1 for (100)[010], (100)[001],(010)[100], (010)[001], (001)[100], (001)[010] shear systems of Ag ! S"#$ Se$ (𝑥 = 0.0, 0.2, 0.4, 0.6, 1.0) based on
Ab initio molecular dynamics (AIMD), where the (KLM)[klm] shear system means that the (KLM) plane is slipped
toward [klm] direction during the shear deformation. As a result, disappearance and restoration of the peak of theradial distribution function between chalcogens during the deformation process were observed for almost all shear
deformations. This implies that the chalcogen sublattice is structurally recovered under shear stress. By analyzing
the movement of chalcogen atoms, we confirmed that structural recovery of the chalcogen sublattice occurs. As
an example, Figure 2 shows the structural recovery of chalcogen atoms during the shear deformation process of(100)[010]. It can be seen that chalcogen atoms, which were initially aligned vertically, tilt in response to
deformation and move collectively in the plane parallel to the deformation direction, reorganizing the vertical lines
and recovering their structure. In doing so, the atomic arrangement is rearranged, as indicated by the color ofatoms above and below the red dotted line. Analysis of the mechanism of structural recovery of the chalcogensublattice revealed that chalcogen atoms move collectively into three planes: 1) a plane that slides during shear
deformation, 2) a plane that is tilted by shear deformation, and 3) a plane that forms a parallelepiped with theabove two planes. In general, atoms can move to the direction in which the distance between atoms is the shortest,
e.g., the [111] direction in the bcc structure. At room temperature, the Ag ! S-type crystal structure is characterized
by the fact that chalcogen atoms are almost equally spaced in all directions. This feature allows the chalcogensublattice of Ag ! S to select the plane and direction of atom transfer for each of the six types of shear deformation,and to recover the structure. In addition to the above structural recovery of chalcogen ions, silver ions have highmobility. This high mobility allows silver ions to flexibly recombine their bonds with surrounding chalcogen ionsand follow the structural recovery of the chalcogen ion sublattice without destroying the crystal structure. This canbe interpreted as the silver ions functioning like free electrons in the metal. Thus, the high mobility of silver ionsenables the structural recovery of the chalcogen ion sublattice, which is thought to be responsible for the ductilityof the inorganic semiconductor Ag ! S"#$ Se$ .
Based on these considerations of ductility due to chalcogen sublattice structure and high mobility silver ions,
it can be predicted that Ag ! Se, which is not ductile at room temperature, is also ductile at high temperature because
the Se sublattice in the superionic conducting phase has a cubic bcc structure and is more isotropic than the S
sublattice in Ag ! S. To verify this, we performed simple shear deformation simulations for Ag ! Se based onclassical molecular dynamics rather than AIMD, using a model potentials that that reproduce the nonsuperionicsuperionic phase transition [3]. In this simulation, the peak of the radial distribution function between seleniums,
which once disappeared during the deformation process, reappeared, confirming that the structure is recovered as
predicted.

Fig. 1. Simple shear deformation that slides the(KLM) plane in the [klm] direction while keeping
the height constant.

Fig. 2. Chalcogen atoms recovering structure during (100)[010] deformation
process. 𝛾 represents the degree of deformation.

References:[1] X. Shi, H. Chen, F. Hao, R. Liu, T. Wang, P. Qiu, U. Burkhardt, Y. Grin, and L. Chen. Nat. Mater. 17, 421-426 (2018).
[2] K. Hirata, T. Matsunaga, S. Singh, M. Matsunami, and T.Takeuchi, J. Electron. Mater. 49, 2895-2901 (2020).
[3] J. P. Rino, Y. M. Hornos, G. A. Antonio, I. Ebbsjö, R. K. Kalia, and P. Vashishta, Chem. Phys. 89, 7542-7555 (1988).

IL5

InvitedWed. 7, Sep. 14:00-14:30

Reverse Monte Carlo modeling: state of affairs and applications to metallic
glasses*

PUSZTAI, László1,21

Wigner Research Centre for Physics, Konkoly Thege út 29-33., Budapest H-1121, Hungary, 2 IROAST,
Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan*
pusztai.laszlo@wigner.hu
Keywords: Reverse Monte Carlo modeling, X-ray/Neutron scattering, microscopic structure, metallic glasses
Reverse Monte Carlo (RMC) [1] is a computer modeling tool that enables us to create large scale, three
dimensional structural models, containing (tens, or even hundreds of) thousands of atomic coordinates. These
structural models are consistent, within errors, with experimental data from neutron and X-ray diffraction,
EXAFS and anomalous X-ray scattering (AXS). The later versions of the RMC computer code [2,3] make itpossible to also include various constraints on, e.g., coordination numbers and angular distributions.
In this contribution, I will briefly introduce the RMC algorithm, then focus on a conundrum very much
relevant to metallic glasses: that of information deficiency. The easiest to understand reason behind thisphenomenon is that for a multicomponent material, such as bulk metallic glass, the number of independent(diffraction, EXAFS, AXS) measurements is practically always lower than the number of partial pair correlationsin the system. In addition, available experimental techniques can provide information only on two-particle
correlations: the validity of structural models must therefore be addressed.
Metallic glasses were among the very first targets of Reverse Monte Carlo modeling [4,5], so it is rather apt
to finish the presentation with showing and analyzing old [5] and new [6,7] results on Pd-based metallic glasses.

References:
1) R.L. McGreevy, L. Pusztai, Molec. Simul. 1, 359 (1988)
2) O. Gereben, P. Jóvári, L. Temleitner, L. Pusztai, J. Optoel. Adv. Mater. 9, 3021 (2007)
3) O. Gereben, L. Pusztai, J. Comput. Chem. 33, 2285 (2012)4) L. Pusztai, Z. Naturf. 46a, 69 (1991)
5) P.A. Duine, J. Sietsma, B.J. Thijsse, L. Pusztai, Phys. Rev. B, 50, 13240 (1994)
6) Hosokawa, S., Berar, J.-F., Boudet, N., Pilgrim, W.-C., Pusztai, L., Hiroi, S., Maruyama, K., Kohara, S., Kato,
H., Fischer, H. E. & Zeidler, A., Phys. Rev. B 100, 054204 (2019)7) Hosokawa, S., Berar, J.-F., Boudet, N., Pilgrim, W.-C., Pusztai, L., Hiroi, K., Kohara, S., Kato, H., Fischer, H.
E. & Zeidler, A., Journal of Non- Crystalline Solids 555, 120536-1-10 (2021)

IL6

InvitedWed. 7, Sep. 14:30-15:00

Long-time and intermittent structural evolution of metallic glasses*

R. Maass1,2, B. Riechers1, A. Das3, Z. Wang1, E. M. Dufresne4, P. M. Derlet5

Federal Institute for Materials Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin, Germany
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois,61801, USA
3
Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY 14853, USA
4
Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
5
Condensed Matter Theory Group, Paul Scherrer Institut, Forschungsstrasse 111, 5232 Villigen PSI, Switzerland*robert.maass@bam.de
Keywords: metallic glasses, aging, relaxation, structural dynamics, x-ray photon correlation spectroscopy
1
2

The advent of x-ray photon correlation spectroscopy (XPCS) allows now for a detailed in-situ exploration of
the structural evolution of metallic glasses. Based on intensity-intensity cross-correlations of coherent speckle
patterns, it is possible to extract time scales that are characteristic of the atomic-scale structural dynamics. Suchdata generates a fundamental understanding of glass dynamics both for the undercooled liquid regime and forglassy solids well below the glass transition temperature, Tg. The increasing body of literature relying on XPCS
presents a consistent picture of stationary structural dynamics well above Tg, but a variety of monotonous andnon-monotonous signatures have been reported in the glassy solid regime at or below Tg. Observed during
step-wise cooling, first evidence of non-monotonous aging, also called intermittent aging, was reported for a
Pd-based metallic glass [1]. Our own work focusing on stress-driven structural dynamics far below Tg also
revealed various signatures of intermittent aging [2, 3]. Surprisingly, this was also the case for a completely
unbiased state along an isotherm at ambient conditions. What could the underlying structural mechanisms forsuch temporal fluctuations of the characteristic momentary time scales be?
In this talk, we shed light onto such intermittent aging signatures via both long-time XPCS experiments andmolecular dynamics simulations. Specifically, we track the temporal fluctuations of aging at 0.98Tg of a Zr-based
bulk metallic glass. Probed over the duration of eight individual experiments of ca. 35000 s each, we reveal
temporal fluctuations of all extracted quantities, including the short-time plateau, the first moment in time, therelaxation time, and the shape parameter. Whilst strong fluctuations of any investigated parameter may appear asa rare event in an individual two-time correlation function, variations over larger timescales emerge as the norm,
which emphasizes the time-scale interplay between an experimental time and a broad distribution of material
timescales. This suggests that aging close to or below Tg is generally a temporal heterogeneous process, if
sufficiently sampled in time. We further observe changes in correlations between the quantified parameters upon
the occurrence of an intermittent aging event, which indicates disruptive collective structural activity. MD
simulations of isothermal annealing and simulated XPCS data complete our effort in understanding temporalfluctuations in the intensity-intensity cross-correlations, implying that much of the seen effects originate fromatomic activity associated with the emergence of structural heterogeneity within the glassy solid.
References:[1] Z. Evenson, B. Ruta, S. Hechler, M. Stolpe, E. Pineda, I. Gallino, R. Busch, Physical Review Letters 115(2015) 175701.
[2] A. Das, P.M. Derlet, C. Liu, E.M. Dufresne, R. Maass, Nature Communications 10 (2019) 5006.
[3] A. Das, E.M. Dufresne, R. Maass, Acta Materialia 196 (2020) 723-732.

IL7

InvitedWed. 7, Sep. 15:00-15:30

Decoupling between thermodynamic and dynamical glass transitions inhigh-entropy metallic glasses
Jing Jiang, Takeshi Wada*, Hidemi Kato
Institute for Materials Research, Tohoku University, Sendai, 980-8577, Japantakeshi.wada.d7@tohoku.ac.jp
Keywords: High entropy metallic glasses, glass transition, α-relaxation*[Introduction]
Glass transition is one of the critical unresolved issues in glassy physics and materials science, at which a
viscous liquid is frozen into the solid state or structurally arrested state. On account of the uniform arrested
mechanism, calorimetric glass transition temperature (Tg) always presents a same tendencywith dynamical glasstransition (or α-relaxation) temperature (Tα). Here, we explored the correlations between the calorimetric anddynamic glass transitions of three prototypical high-entropy metallic glasses (HEMGs) systems. We found that
HEMGs present a depressed dynamical glass transition phenomenon, i.e. HEMGs with moderate Tg represent
the highest Tα and the maximum corresponding activation energy. This decoupled glass transitions areassociated with the high mixing entropy effect and the induced nanoscale spatial homogeneity. The results have
implications for understanding the high mixing entropy effect on dynamics of metallic glasses for designing new
metallic glasses with plenteous physical and mechanical performances.
[Experimental]
Master alloys were prepared by arc-melting mixtures of raw metals (purity: >99.9 mass %) in an Ar
atmosphere purified with a Ti getter. Ribbon specimens were obtained via a melt spinning technique. Threesystems were designed, La (Ce)-based, Pd (Pt)-based and Zr (Hf)-based, to compare the behaviors of highentropy and low entropy metallic glasses. The microstructure was observed by X-ray Diffraction, ScanningElectron Microscopy combined with energy dispersive X-ray spectroscopy and Transmission Electron
Microscopy. The thermal characters were detected by the Differential Scanning Calorimetry (DSC). The
dynamic processing was performed by the Dynamic Mechanical Analyzer (DMA).
[Results]
Differential scanning calorimeter (DSC) traces shows obvious glass transition and crystallization signals
confirm the glassy state of the three samples. LaCe-HEMG with the highest ∆Smix yields an intermediate valueof Tg. MGs exhibit multi-complex relaxation dynamics, α-relaxation as the main relaxation mode is directly
related to the viscous flow and the glass transition. With Ce half replacing La, LaCe-HEMG exhibits the highest
α-relaxation temperature Tα, which is not synchronous with the calorimetric Tg. According tothe conventional
wisdom, a glass with a higher Tg always poses higher difficulty in activation of α-relaxation and thus has alarger value of Tα. Nevertheless, LaCe-HEMG, with the modest thermodynamic devitrification behavior,performs the uppermost dynamic glass transition process.

IL8

InvitedWed. 7, Sep. 15:50-16:20

Structure Determination in a new Type of Amorphous Molecular Solids with
Extreme Nonlinear Optical Properties*

W.-C. Pilgrim1, B. D. Klee1,2, J. R. Stellhorn1,3, J. Link Vasco1, K. Volz1, A. Zeidler5,
S. Hosokawa4, B. Paulus1 and S. Dehnen11Philipps-University, Marburg, 35032, Germany, 2 Wigner Research Centre for Physics, Budapest, H-1121,
Hungary, 3 Hiroshima University, Hiroshima, 739-8527, Japan, 4 Kumamoto University, Kumamoto, 860-8555,
Japan, 5Univerity of Bath, Bath, BA2 7AY, UK*
pilgrim@staff.uni-marburg.de
Keywords: molecular amorphous solids, molecular RMC-simulation, White-Light-Generator, X-ray and neutron
scattering.

A new class of molecular cluster material has recently been synthesized exhibiting extreme nonlinear opticalbehavior when irradiated just by an inexpensive continuous wave infrared laser diode.1) The molecular building
blocks consist of adamantane-like cluster units of general formula [(RX)4Y6], where X is a group-14 element, Y isa chalcogen and R is an organic ligand attached to a group 14 atom. The shape of these materials is displayed in
the insets of the Figure, where the organotin and the organosilicon sulfide clusters [(PhSn)4S6] and [(PhSi)4S6] arerespectively shown, with phenyl (Ph) ligands (-C6H5) attached to the Sn and Si atoms. The materials can besynthesized comparatively easily and variation of the ligands and/or the chalcogens or of the group 14 element
allows great chemical variability of the cluster composition. A large number of derivatives has now beensynthesized as easy-to-handle powders. All of them either act as second harmonics generators (SHG) or as WhiteLight-Generators (WLG), the latter providing a brightwhite optical emission.2) The visible part of such
spectra resembles the color of a tungsten-halogen lamp
at about 2900 Kelvin and the emitted beam retains theexcellent beam divergence of the driving laser.
However, the morphology of the substance has asignificant impact on the type of response. While
crystalline compounds clearly react as SHGs, only
amorphous materials respond as WLGs. This isexemplary demonstrated for two of these systems in
the Figure. The two compounds differ only by theexchange of Sn by Si in the cluster core, but they showcompletely different optical and morphologicalproperties. The Figure shows the optical answers if
being irradiated by a 980 nm laser-line (1.265 eV).
While the Si-based compound replies with a distinct
2nd order harmonics at 2.53 eV (a), the Sn-containing
material emits a broad white spectrum ranging from
NLO-responses from (a) the crystalline [(PhSi)4S6] and (b) the
about 1.5 to 3 eV (b). Also shown are the respective
amorphous [(PhSn)4S6], respectively (top). The driving
diffraction-patterns of the two substances. The
excitation is visible at 1.265 eV. The 2nd-harmonic of (a) isseen at 2.53 eV, while (b) depicts a broad white spectrum. The[(PhSi)4S6] material is clearly crystalline, indicated by
X-ray patterns are also shown below indicating that the SHGthe Bragg peak dominated diffractogram, whilematerial is crystalline (left) while the WLG material (right)[(PhSn)4S6] is fully amorphous and the scattered Xshows the typical S(Q) of an amorphous solidrays yield a structure factor S(Q), typical of a fully
disordered system. Hence, disorder seems to be a
mandatory requirement for the WLGs. The fact that WLG is never observed from crystalline cluster materials
indicates that the effect is enabled by microscopic structural correlations or degrees of freedom which are only
accessible in a sufficiently disordered state. To understand this, we have developed a new code to perform
molecular Reverse Monte Carlo simulations and we have started a comprehensive exploration on the structuralproperties of the WLG materials using scattering and EXAFS experiments. We will report on the current state ofresearch on the amorphous WLG materials and we will present our findings regarding structural differences
between SHG and WLG materials.
1) N. W. Rosemann, J. P. Eußner, A. Beyer, S. W. Koch, K. Volz, S. Dehnen, and S. Chatterjee,
Science 352, 1301 (2016).
2) S. Dehnen, P. Schreiner, S. Chatterjee, K. Volz, N. W. Rosemann, W.-C. Pilgrim, D. Mollenhauer,
and S. Sanna, ChemPhotoChem 5, 1 (2021).

O14

Wed. 7, Sep. 16:20-16:40

Static Structure of Liquid Ag2Se Based on Molecular Dynamics Simulations
Using Artificial Neural Network Potential*

Akihide Koura1, Kohei Shimamura1, Fuyuki Shimojo1

1

Department of Physics, Kumamoto University, Kumamoto, 860-8555, Japankoura@tech.kumamoto-u.ac.jp
Keywords: Liquids, Ab initio simulation, Machine learning, Molecular dynamics, Ag2Se.

*

Silver chalcogenides (Ag2Se, Ag2S, and Ag2Te) are important materials for thermoelectric devices, which
contribute to capture/reuse waste heat. They have hish Seebeck coefficient and low thermal conductivity [1,2].
These features are suitable for the devices. It is reported that the thermal conductivity has a peak at around phasetransition temperature between non-superionic and superionic phases [1,2]. In the superionic phase, Ag atoms
migrate in the chalcogen sublattice even in the crystalline state. In order to clarify the mechanism of suchinteresting properties, many experimental and theoretical studies have been reported so far. On the other hand, thenumber of structural studies on liquid silver chalcogenides are not reported so much. For example, details of thestatic structure of liquid Ag2Se was reported with the neutron scattering measurements [3] and the molecular
dynamics (MD) using empirical potential and the ab initio molecular dynamics (AIMD) simulations [4]. The
theoretical result [4] is in good agreement with the experimental result [3], however, it is necessary to be careful
to discuss based on these studies due to the system size of theoretical study consisting of only 69 atoms [4].
To study the static and dynamic properties Ag2Se with computer simulations, it is necessary to solve thecalculation cost problem. Using AIMD simulations, the precise calculation can be performed in principle, however,the calculation cost is extremely high. Although MD simulations with empirical potentials are quite faster than
AIMD simulations, making potential functions is difficult. In recent years, the machine learning based on the resultof AIMD simulations to construct an interatomic potential is developed with the artificial neural network (ANN)[5]. MD simulations with ANN potential (ANN-MD) is actually slower than typical empirical MD simulations,however, it enables us to perform the fast calculation with the high precision as same as AIMD simulations.
In this study, we focused on the static and dynamic
properties of liquid Ag2Se based on the ANN-MD
simulations. We used a 384-atom system (256 Ag + 128 Se).
Training data, i.e., AIMD simulations were performed at
1200 K with our previous condition of the Hubbard
correction for Ag atoms [6]. The total simulation time oftraining data was 9.4 ps with the time step of 2.4 fs. ANNMD simulations were executed at least 240 ps with thecanonical ensembles. Figure 1 shows the partial radial
distribution functions (PRDFs) 𝑔𝑔𝛼𝛼𝛼𝛼 (𝑟𝑟) of liquid Ag2Se
obtained by ANN-MD and AIMD simulations drawn withblack solid and red dashed lines, respectively. The blue circle
shows the experimental result [3]. Peak positions of PRDFs
𝑔𝑔AgSe (𝑟𝑟) and 𝑔𝑔SeSe (𝑟𝑟) obtained by AIMD and ANN-MD
are in reasonable agreement with those by experimental
result. 𝑔𝑔AgAg (𝑟𝑟) obtained by simulations are different fromthe experimental result. ANN-MD simulations well
reproduced AIMD except for the Se-Se correlation. In thepresentation, we will discuss details of static structure,bonding and dynamic properties obtained by AIMD and
ANN-MD simulations.
Figure 1 Partial radial distribution functions 𝑔𝑔𝛼𝛼𝛼𝛼 (𝑟𝑟) of

liquid Ag2Se. Black and red lines correspond to the result ofReferences:
ANN-MD and AIMD simulations, respectively. The blue
[1] K. Hirata, T. Matsunaga, S. Singh, M. Matsunami, and T.
circle shows the experimental result [3].
Takeuchi, J. Elec. Mater. 49, 2895 (2020).
[2] K. Hirata, T. Matsunaga, S. Singh, M. Matsunami, and T.
Takeuchi, Mater. Trans. 61, 2402 (2020).
[3] A. C. Barnes, S. B. Lague, P. S. Salmon, and H. E. Fischer, J. Phys.: Condens. Matter 9, 6159 (1997).
[4] F. Kirchhoff, J. M. Holender, and M. J. Gillan, Phys. Rev. B 54, 190 (1996).
[5] N. Artrith, A. Urban, Comput. Mater. Sci. 114 (2016) 135.
[6] S. Fukushima, M. Misawa, A. Koura, and F. Shimojo, J. Phys. Soc. Jpn. 88, 115002 (2019).

O15

Wed. 7, Sep. 16:40-17:00

Semianalytic Formula for Multiphonon Thermal Diffuse Scattering in Solids
Hikaru Kitamura
Department of Physics, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japankitamura@scphys.kyoto-u.ac.jp
Keywords: Static structure factor, Thermal diffuse scattering, Phonon, Debye-Waller factor, Powder diffraction
A new semianalytic formula for the static structure factor S(k) of polycrystalline and amorphous solids atelevated temperatures, applicable to the entire wavenumber (k) range, is presented. Particular attention is paid
to the contribution from thermal diffuse scattering (TDS) due to phonons, STDS(k), where multiphonon processes
beyond the one-phonon term are taken into account up to infinite order within the Debye model. It is thereby
proven that the one-phonon TDS accounts for the compressibility relation in the k = 0 limit as well as thelogarithmic singularity at the Bragg points, whereas the multiphonon TDS ensures the convergence of S(k)towards unity at large k. The present formula is computationally efficient, requiring only a one-dimensionalradial integration of the elastic scattering part of the structure factor Sel(k) and the kernel function (see Fig. 1);
the latter is expressed analytically in terms of the atomic density n, average sound velocity, and the
Debye-Waller exponent W(k). A numerical example for a face-centred-cubic polycrystal near the melting pointis exhibited in Fig. 2; significance of the multiphonon contribution is clearly indicated. Comparison with theprevious formula by Meisel and Cote1) will be discussed.
References:
1) L.V. Meisel and P.J. Cote, Phys. Rev. B 16, 2978 (1977).

Fig. 1. Structure of the semianalytic formula for S(k).

Fig. 2. TDS structure factor for fcc polycrystal near the melting point, witha denoting the lattice constant. Full result is indicated by the red curve(‘all phonons’), whereas the blue curve represents the one-phonon
contribution. The first eight Bragg peaks are indicated by vertical bars andMiller indices (hkl).

RIL1

InvitedThu. 8, Sep. 16:00-16:30 JST
9:00-9:30 CEST

Dynamic properties of liquids of interest in nuclear energy production:liquid Li-Pb alloys and molten UO2 .
*L. E. González, B. G. del Rio, D. J. González

Dept. Física Teórica, Universidad de Valladolid, Valladolid, 47011, Spain*luisen@metodos.fam.cie.uva.es
Keywords: Ab initio simulation, liquid structure, dynamics.
Li-Pb alloys and UO2 are systems of technological interest in the field of energy production through nuclear
reactions. The liquid alloy at the Pb-rich eutectic composition is a strong candidate to be used as breedingblanket in tokamak fusion reactors, while the study of the properties of molten uranium dioxide is important interms of risk asessment in fission reactors.
From the physical point of view, Li-Pb alloys and uranium dioxide share some common characteristics, suchas a large mass disparity between their components. We have also recently observed [1] that, at thestoichiometric composition Li4Pb, the liquid structure (like the solid one at a nearby composition) can be
described in terms of interconnected polyhedra, which is a structural feature typical of molten (and solid) oxides.
But they also show some large discrepancies, with a melting temperature lower than 1000 K for Li-Pb alloys andlarger than 3000 K for UO2, due to a strong difference between the bonding type in both systems (metallic in LiPb alloys, ionic/semiconducting in UO2 ). It is therefore interesting to compare also the dynamic properties ofboth systems, in particular the effect that such different bonding characteristics may have on features like theparticular type of “fast sound” phenomenon that was observed for the first time in Li4Pb several decades ago.
The accurate description of the forces involved in the dynamics, obtained from first principles, enables us to
study with confidence the atomic trajectories so as to compute the longitudinal and transverse collective dynamic
properties, which are analyzed and compared with some theoretical approaches. We also present some results forother less commonly studied magnitudes such as the cage correlation functions. We finally discuss thelimitations inherent to the method employed and possible alternatives that preserve the accuracy of the forces.

References[1] M.M.G. Alemany, J. Souto-Casares, L.E. González and D.J. González, J. Molec. Liq. 344, 117775 (2021).

RCL1

Committee

Thu. 8, Sep. 16:30-17:00 JST
9:30-10:00 CEST

Origin of Positive Sound Dispersion in Simple Liquids and Liquid Alloys*

Taras Bryk1,21Institute for Condensed Matter Physics of NASU, Lviv, 79011, Ukraine, 2 Lviv Polytechnic National University,
Lviv, 79013, Ukraine*
bryk@icmp.lviv.ua
Keywords: collective excitations, positive sound dispersion, generalized hydrodynamics, eigenmode analysis,computer simulations
I will review recent theoretical approaches for explanation of positive sound dispersion (PSD – a bending of
the dispersion curve of collective excitations beyond the hydrodynamic regime towards higher frequencies) inliquids and will present results of a very recent eigenmode analysis for density-density time correlation functions
in simple fluids, liquid metals and binary liquid alloys.
The eigenmode analysis enables an estimation of mechanisms of sound propagation on different spatial
scales: k-dependent contributions from different types of fluctuations to eigenvectors corresponding to soundexcitations provide very clear picture of dynamic processes responsible for sound propagation in and outside thehydrodynamic regime. Two dynamic models were used for the eigenmode analysis: viscoelastic and thermoviscoelastic ones [1,2]. The k-dependent eigenvectors of sound eigenmodes make evidence that the change fromhydrodynamic mechanism (due to conservation laws) to the elastic one is taking place via a gradualreplacement of contribution from density fluctuations by a contribution from stress fluctuations. For large wave
numbers the longitudinal and transverse (shear) collective excitations propagate solely due to coupled masscurrent and stress fluctuations. Namely this gradual replacement of the contribution from conserving density
fluctuations by the one coming from stress fluctuations is responsible for emergence of the positive sounddispersion. Another very important consequence of this eigenmode analysis is a prediction when the slowest
relaxation mode shows a crossover from thermal relaxation (hydrodynamic regime) to non-hydrodynamic
structural relaxation [3] with increasing wave number, that should be observed in behavior of the central peak ofexperimental dynamic structure factors S(k,ω).
For the case of liquid binary alloys additional crossover takes place because of interaction of sound modes
with concentration fluctuations and overdamped optic-like modes.

References:1) I.M. de SCHEPPER, E.G.D. COHEN, C. BRUIN, J.C. van RIJS, W.MONTFROOIJ and L.A. de GRAAF,
Phys. Rev. A 38, p 271 (1988).
2) T. BRYK, I. MRYGLOD, T. SCOPIGNO, G. RUOCCO, F. GORELLI and M. SANTORO, J. Chem.
Phys. 133, p 024502 (2010).
3) T. BRYK, Eur. Phys. J. Special Topics 196, p 65 (2011)

RCL2

Committee

Thu. 8, Sep. 17:10-17:40 JST
10:10-10:40 CEST

Chemical short-range order in undercooled Cu-Ni melts*

Dirk Holland-Moritz1, Fan Yang1, Thomas Hansen2, Florian Kargl1

1

Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Materialphysik im Weltraum, 51170 Köln,
Germany, 2 Institut Laue-Langevin (ILL), 38042 Grenoble, France*
dirk.holland-moritz@dlr.de
Keywords: Short-range order, Demixing, Neutron scattering
For liquid Cu-Co, which shows a rich phase diagram, it has been shown that Cu and Co demix, if the liquid isundercooled below its binodal line. In contrast Ni-Cu shows a comparatively simple phase diagram of a solid
solution and no phase separation in liquid state has been reported so far. On the other hand, measurements of theelectrical resistivity show a non-linear temperature dependence for melts of the Cu-rich alloys Ni40Cu60 and
Ni20Cu80 [1]. A possible explanation for this non-linear temperature dependence might be concentration
fluctuations that increase with increasing undercooling of the liquid, hence indicating a tendency for demixing.
Also the slightly positive enthalpy of mixing of Ni-Cu points towards a demixing nature of this system.
While these are indirect arguments, in this work we present direct investigations on the short-range order in
Ni42.5Cu57.5 alloy melts by elastic neutron diffraction that have been performed on the D20 diffractometer at theInstitute Laue-Langevin. An electromagnetic levitation furnace was used as sample environment allowing toundercool the melts below the melting temperature [2]. Partial structure factors have been determined byapplication of an isotopic substitution technique using samples of the four different isotopic compositions
58
Ni42.5natCu57.5, 60Ni42.5natCu57.5, natNi42.5natCu57.5 and 62Ni42.563Cu57.5.
The Bhatia-Thornton partial structure factor SNN that describes the topological short-range order of the melt
closely resembles the structure factors observed for melts of the pure elements Ni [3] and Cu, indicating asimilar topological structure. For the Bhatia-Thornton partial structure factor SCC that describes the chemical
short-range order of the melt a rise in intensity is observed at low momentum transfer, q, on top of a relatively
large flat background with some smaller oscillations towards larger q. The rise of SCC at low q increases withdecreasing temperature. It directly points to the demixing nature of the system with concentration fluctuations onlarge length scales that become more pronounced with increasing undercooling.
Interestingly, the generic behavior of phase separation has recently been studied by means of molecular
dynamics simulations on binary symmetric Lennard-Jones mixtures [4,5]. A demixing behavior has been foundfor attractive Lennard-Jones liquids, if the interaction parameters of the unlike atomic pairs are smaller thanthose of the like atomic pairs. The shape of SCC and its temperature dependence calculated by the molecular
dynamics simulations closely resemble those we observed experimentally for liquid in Ni 42.5Cu57.5 showing thatmain predictions on the dependence of the chemical short-range order on the atomic interactions inferred fromthis simple generic model are found in real metallic systems like Cu-Ni.
References
1) T. Richardsen, G. Lohöfer, Int. J. Thermophys. 23, 1207 (2002).
2) D. Holland-Moritz et. al., Meas. Sci. Techn. 16, 372 (2005).
3) T. Schenk et al., Phys. Rev. Lett. 89, 075507 (2002).
4) S.K. Das et al., J. Chem. Phys. 125, 024506 (2006).
5) S. Amore et al., J. Chem. Phys. 134, 044515 (2011).

RO1

Thu. 8, Sep. 17:55-18:15 JST
10:55-11:15 CESTThe Short-Range Order in Liquid Water*

Neta Ellert1, Guy Makov1

1

Materials Engineering Department, Ben-Gurion University of the Negev, 84105 Beer-Sheva, Israel
netani@post.bgu.ac.il
Keywords: short range order, liquids, water, Quasi Crystalline Model.

*

The short-range order in water was determined from experimentally measured partial radial distributionfunctions by applying the Quasi Crystalline Model (QCM), an approach to analyzing the short-range order inliquids and amorphous systems, which employs a structural model to determine the short-range order of a liquid
directly from the radial distribution function. This model uses a reference lattice structure to generate ahypothetical amorphous radial distribution function that is compared with the radial distribution function
obtained from experiments or simulations. The short-range order of the amorphous system is identified with thespecific reference lattice producing the best fit for the data.
Three partial radial distribution functions were analyzed for water at several pressures and temperatures. It was
found that at low temperatures and pressures, the short-range order of water is similar to that of the hexagonalice (Ih) structure. At higher pressures and low temperatures, the short-range order of water becomes similar tothat of tetragonal ice III structures with c/a ratio of 0.8. At higher temperatures of 573K, the short-range orderobtained was similar to that of rhombohedral ice II.
An example for a successful fit of the partial O-O radial distribution function at ambient conditions is shown
below:

Figure 1 The QCM of water at ambient conditions., RDF of partial O-O modeled by the QCM using the ice Ihstructure with c/a=1.5

RO2

Thu. 8, Sep. 18:15-18:35 JST
11:15-11:35 CEST

Impact of sulfur addition on the structure and dynamics of Ni-Nb alloys
N. Grund1, *F. Yang1, D. Holland-Moritz1, L. Ruschel2, B. Adams2, T. Buslaps3, S. Banerjee4,
R. Busch2, A. Meyer11Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt, Cologne, 51170,
Germany,2
Lehrstuhl für metallische Werkstoffe, Universität des Saarlandes, Saarbrücken 66123, Germany,3
European Synchrotron Radiation Facility (ESRF), Grenoble 38043, France,4
Deutsches Elektronen-Synchrotron (DESY, Hamburg 22607, Germany*
fan.yang@dlr.de
Keywords: sulfur bearing alloys, electrostatic levitation, synchrotron X-ray diffraction.

Bulk metallic glasses feature an amorphous structure, which results in exceptional properties as engineering
materials. Typically alloying additional components improves the glass forming ability (GFA). Beside adding
non-metallic elements like P, B, C, recently sulfur has been found to facilitate bulk metallic glasses formation at
different concentration levels [1]. This makes them promising candidates for commercialization, where the alloy
composition can be tuned according to applications. In the case of the binary Ni62Nb38 glass forming alloy, it has
been found that an optimal enhancement of the GFA can be achieved by alloying only 3 at% S. Such kind of“minor alloying” effects cannot be understood by applying the common empirical rules like a denser packing of
the melt, or the formation of deep eutectic compositions.
Employing electrostatic levitation combined with in-situ synchrotron diffraction, we studied impacts of sulfur
on the structure and dynamics of Ni-Nb based alloys, as well as on the solidification behavior from undercooled
melt. First results show that small, but notable changes can be observed in the measured liquid structure factor
upon an addition of 3 at% S. In particular, in the obtained X-ray total structure factor the position of the firststructure factor maximum appears to shift towards lower q values. The structure changes are analyzed with thehelp of the partial structure factors of the binary Ni-Nb alloy [2]. It has been also observed that the initial phases
solidified from the undercooled melt seem to be different with and without S. The implication of these changes
on the glass forming behavior is discussed together with the melt viscosity measured using the oscillating drop
technique.
References:[1] A. Kuball, O. Gross, B. Bochtler, R. Busch, Scr. Mater. 146, 73-76 (2018).
[2] D. Holland-Moritz, F. Yang, J. Gegner, T. Hansen, M. D. Ruiz-Martín, and A. Meyer, J. Appl. Phys. 115,
203509 (2014).

RIL2

InvitedThu. 8, Sep. 20:00-20:30 JST
13:00-13:30 CEST

Cluster-plus-glue-atom Model and the Thus-obtained Composition Genes for
Metallic Glasses
Chuang Dong1,2, Shuang Zhang1, Cunlei Zou1, Chenxi Dong1, and Yajun Zhao1*
1

School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China;
Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology),
Ministry of Education, Dalian 116024, China.
*
dong@djtu.edu.cn
Keywords: Metallic glasses, Cluster-plus-glue-atom model, Molecule-like structural units, Composition genes,
Composition design.
2

Composition interpretation of metallic glasses with high glass-forming abilities is an important issue, which
relies on insights into their complex atomic structures. Metallic glasses, especially bulk metallic glasses, do havespecific compositions, which strongly suggest the possible existence of some molecule-like structural units, inwhich the versatile but specific compositions are rooted. These structural units mimic the molecules in chemical
substances but generally differ from the crystallographic unit cells. The possibility of having these fundamental
units has been apparently overlooked because of the lack of structural models to properly address the short-rangeorder in metallic glasses. A simplified atomic picture for short-range order is therefore required to identify themolecule-like composition units, in combination with an electronic factor for the concern of the structural
stability.
Our research group has already proposed the cluster-plus-glue-atom model in 2007, which is a
short-range-order structural model that renders any structure with a structural unit containing the essential
structural information of the whole system. From the nomination of this model, one immediately determines amolecule-like structural unit consisting of a nearest-neighbor cluster plus a few outer-shell glue atoms. Actually,such structural unit, serving as the composition carrier, can be seen as the composition gene of the material. The
proposition of composition genes facilitates the understanding of prevailing metallic glasses and can be a useful
tool to guide the exploration of new composition space. With aides of the cluster-plus-glue-atom model and thethus-obtained molecule-like structural units (or said composition genes), fairly accurate compositioninterpretation and eventually design of metallic glasses with large glass-forming abilities could be envisaged.

RO3

Thu. 8, Sep. 20:30-20:50 JST
13:30-13:50 CEST

Composition Optimization Based on Cluster-plus-glue-atom Model for Bulk
Metallic Glass Zr55Cu30Al10Ni5
Shuang Zhang1, Cunlei Zou1, Yajun Zhao1, Chenxi Dong1, and Chuang Dong1,2*
1School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China;
Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology),
Ministry of Education, Dalian 116024, China.
*zhangshuang@djtu.edu.cn
Keywords: Bulk metallic glass Zr55Cu30Al10Ni5, Composition origin, Composition optimization,
Cluster-plus-glue-atom model, Dual-cluster formalism.
2

Previously we have proposed the cluster-plus-glue-atom model, by introducing a new description method
based on the short-range-order structural units. In this model, good glass formers satisfy the general formula[cluster](glue atom)1 or 3, where the cluster is the nearest-neighbor coordination polyhedron with a central atomand the glue atoms are situated between the clusters. Thereof, the dual-cluster formalism is developed, whichassumes that a complex material may consist of two subunits, each being expressed by a cluster formula. Thus,
the structural unit of a multi-element metallic glass can be deciphered to be composed of two clusters from basic
binary crystalline phases plus 2, 4, or 6 glue atoms.
In the present work, the bulk metallic glass Zr 55Cu30Al10Ni5 is taken as a typical example of quaternarycomplex systems, and the cluster-plus-glue-atom model is extended to the dual-cluster case to conduct thecomposition interpretation. Combing the cluster-based composition analysis method and the 24-electron rule for
ideal metallic glasses, the composition origin of the bulk metallic glass Zr 55Cu30Al10Ni5 is revealed and a seriesof possible new compositions are designed. Finally, higher glass forming ability is exhibited experimentally,
indicating the achievement of composition optimization. This work provides a quantifiable composition design
method for multi-element metallic glasses.

RO4Thu. 8, Sep. 20:50-21:10 JST
13:50-14:10 CEST

Colorless and high refractive SnO- and Sb2O3-containing borosilicate glasses
Kazuki Mitsui1, *Akira Saitoh1,
1

Graduate School of Science and Engineering, Ehime University, Matsuyama, Ehime 790-8577, Japan
asaito@ehime-u.ac.jp
Keywords : Oxide glasses, Structure, Transparency, Refractive index.

*

We studied a relationship between the structure and optical properties in SnO- and Sb2O3-containingborosilicate glasses. Recently, PbO containing oxide glass has been excluded from optical devices such as lenses
and optical fibers, caused by its toxicity. Instead, Bi2O3 containing oxide glasses show the high refractive andsmall photoelastic properties that meet an optical criterion about lenses and filters 1). However, one of the
drawbacks is a coloration in the visible range attributed to the mid-gap absorption 2). A notion is to choose Sb2O3
oxide as a co-dopant since no absorption derived from 5s2-5s1p1 bands exists.
Fig. 1 shows transmission spectra of SnO andSb2O3-containing borosilicate glasses. Meanwhile,these glasses exhibit a high refractive index(~1.8) and very small photoelastic constant (±0.05 × 10−12 Pa−1). The optical absorption edge isblue-shifted with increasing of B2O3. The optical
bandgap of the 55SnO−45B2O3 glass is about 3.6
eV. The micro-Raman scattering spectra
elucidates that a four-coordinated borate unit
(BO4) exists in the SnO and Sb2O3-containing
glass systems. Then, a blue-shift occurs by
substitution of B2O3 by SiO2 in SnO-containingborosilicate glasses. This may corroborate thatthe tetrahedral BO4 units with non-bridging
oxygens are selectively coordinated to a Sn2+ ion,resulting in a weak ligand.
Fig.1. Transmission spectra of xSnO–yB2O3–(100–x–y)SiO2(upper), and xSb2O3–yB2O3–(100–x–y)SiO2 (lower) glasses
with 1-mm thickness show very small PEC values.

References
1) R. Morena, J. Non-Cryst. Solids 263, 382 (2000).
2) A. Saitoh, K. Hayashi, K. Hanzawa, S. Ueda, S. Kawachi, J. Yamaura, K. Ide, J. Kim, G. Tricot, S. Matsuishi,
K. Mitsui, T. Shimizu, M. Mori, H. Hosono, and H. Hiramatsu, J. Non-Cryst. Solids 560, 120720 (2021).
#

Present address: Graduate School of Science and Engineering, Ehime University, Matsuyama, Ehime 790-8577,
Japan

RIL3

InvitedThu. 8, Sep. 21:20-21:50 JST
14:20-14:50 CEST

Understanding diffraction patterns of glassy, liquid and amorphous materials via
topological analyses*

Yohei Onodera1,2, Shinji Kohara2

1

Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010 Asashiro-nishi, Kumatori-cho,Sennan-gun, Osaka 590–0494, Japan, 2 Research Center for Advanced Measurement and Characterization,
National Institute for Material Science, 1-2-1 Sengen, Tsukuba, Ibaraki, Tsukuba 305–0047, Japan*y-onodera@rri.kyoto-ac.jp
Keywords: structure, X-ray/Neutron diffraction, reverse Monte Carlo simulation, classical molecular dynamics
simulation, topological analyses.

S(Q)The structure of glassy, liquid and amorphous materials is still not well understood, due to the insufficient
structural information from diffraction data. Here, attempts are made to understand the origin of diffraction peaks
in disordered materials. Furthermore, we applied topological analyses to reveal the relationship between diffraction
pattern and topology of disordered materials1).
Figure 1 shows total structure factors, S(Q), for disordered
Q1 Q2
Q3
materials whose structure contains tetrahedral motifs obtained(FSDP) (PP)by neutron diffraction (ND) and X-ray diffraction (XRD). All
7
amorphous and glassy materials form a tetrahedral network
a-Si (XRD)
whereas two liquids are molecular liquids in which CCl4 and P4
6
tetrahedra are isolated. As can be seen in the fiture, a three-peak
g-ZnCl2 (ND)
structure, the first sharp diffraction peak (FSDP, Q1), the5principal peak (PP, Q2), and the third peak (Q3), can be observedin the S(Q) except a-Si. It is confirmed that the FSDP is not a
g-GeSe2 (ND)
4signature of the formation of a network, because an FSDP isobserved in molecular liquids. The FSDP appears as the result
g-GeS2 (ND)
3of a sparse distribution of planes in polyhedra by analyzing theatomic configuration for g-SiO2 generated by a combination ofg-GeO2 (ND)2reverse Monte Carlo (RMC)10) and molecular dynamics (MD)simulations. It is found that the PP reflects orientationalg-SiO2 (ND)1correlation of polyhedra. Q3, that can be observed in all
disordered materials, stems from simple pair correlations.
l-CCl4 (ND)
Moreover, information of the topology of disordered materials
0
was revealed by utilizing persistent homology11) analyses. The
l-P (XRD)
persistence diagram of silica (SiO2) glass suggests that the-1
shape of rings in the glass is similar not only to those in the
crystalline phase with comparable density (α-cristobalite), but
-2
0
5
10
15
20
25
also to rings present in crystalline phases with higher density
QrA-X(α-quartz and coesite); that is thought to be a signature of goodglass-forming ability in SiO2 glass. Our series of analyses Fig. 1. Total structure factors, S(Q), for amorphous (a)-Si2),
demonstrated that a combination of diffraction, computer glassy (g)-ZnCl23), g-GeSe24), g-GeS25), g-GeO26), g-SiO27), l9)8)simulation and topological analyses is a useful tool to uncover CCl4 , and l-P . The scattering vector Q is scaled bystructural features hidden in halo pattern of disordered multiplying by rA-X (distance between center and corner oftetrahedra. In the case of l-P, rA-X is estimated from the sidematerials.
length of P4 tetrahedron).
References:
1) Y. Onodera et al., J. Ceram. Soc. Jpn. 127, 853 (2019).
2) K. Laaziri et al., Phys. Rev. Lett. 82, 3460 (1999).
3) A. Zeidler et al., Phys. Rev. B 82, 104208 (2010).
4) E. Bychkov et al., Phys. Rev. B 72, 172107 (2005).
5) A. Bychkov et al., Phys. Chem. Chem. Phys. 15, 8487 (2013).
6) A. C. Hannon et al., J. Phys. Chem. B 111, 3342 (2007).
7) A. C. Hannon, Encyclopedia of glass science, technology, history and culture, John Wiley & Sons Inc, 129(2021).
8) H. Morita et al., J. Mol. Liq. 147, 182 (2009).
9) Y. Katayama et al., Nature 403, 170 (2000).
10) R. L. McGreevy and L. Pusztai, Mol. Simul. 1, 359 (1988).
11) Y. Hiraoka et al., Proc. Natl. Acad. Sci. USA 113, 7035 (2016).

RO5

Thu. 8, Sep. 21:50-22:10 JST
14:50-15:10 CEST

Local structural investigation of non-crystalline materials at high pressure

Xinguo Hong
Center for High Pressure Science and Technology Advanced Research, Beijing 100094, P.R. China*xinguo.hong@hpstar.ac.cn and xinguo.hong@gmail.com
ABSTRACT
Local structure plays an dominant role in the structural polyamorphsim and novel electronic
properties under extreme conditions[1-4]. Liquids and disordered solids under extreme conditions in the
Earth interior is important for Earth and planetary science. However, measurement of the local structureof non-crystalline materials at high pressure remains a challenge. Recently we have succeeded in obtainhigh-quality atomic pair distribution function (PDF) using high-energy X-ray microbeam[5] and X-ray
absorption fine structure at high pressure[1,6].
PDF is a powerful local-structural tool for studying crystalline, disordered and nano materials [713]. The total scattering, including Bragg peaks as well as diffuse scattering, contributes to the PDF, and isparticularly useful for characterizing the local structure of amorphous materials, e.g. ref. [14] and theaperiodic distortions in crystals as well [10]. XAFS is a well-known local structural tool, which can provide
an upper level resolution in the short order of local structure, being able to probe the subtle structural andelectronic polymorphs[3,4,15]. In this conference, we will report our recent progress in the high-energy Xray focusing, HP-PDF and HP-XAFS, and the related first-principles calculations.
References:[1]
X. Hong, M. Newville, T. S. Duffy, S. R. Sutton, and M. L. Rivers, Journal of Physics: Condensed Matter 26,
035104 (2014).
[2]
X. Hong, L. Ehm, and T. S. Duffy, Applied Physics Letters 105, 081904 (2014).
[3]
X. Hong, M. Newville, Y. Ding, D. Zhang, T. Irifune, G. Gu, and H.-K. Mao, Physical Review B 102, 134110(2020).
[4]
X. Hong, M. Newville, Y. Ding, T. Irifune, G. Gu, and H.-K. Mao, Physical Review B 101, 214107 (2020).
[5]
X. Hong, L. Ehm, Z. Zhong, S. Ghose, T. S. Duffy, and D. J. Weidner, Scientific Reports 6, 21434 (2016).
[6]
X. Hong, M. Newville, V. B. Prakapenka, M. L. Rivers, and S. R. Sutton, Review of Scientific Instruments
80, 073908 (2009).
[7]
T. Egami and S. J. L. Billinge, Pergamon, Oxford (1994).
[8]
J. L. Billinge Simon, in Zeitschrift für Kristallographie/International journal for structural, physical, andchemical aspects of crystalline materials2004), p. 117.
[9]
T. Proffen, R. G. DiFrancesco, S. J. L. Billinge, E. L. Brosha, and G. H. Kwei, Physical Review B 60, 9973
(1999).
[10]
S. J. L. Billinge and M. G. Kanatzidis, Chemical Communications, 749 (2004).
[11]
S. J. L. Billinge and I. Levin, Science 316, 561 (2007).
[12]
B. Gilbert, F. Huang, H. Zhang, G. A. Waychunas, and J. F. Banfield, Science 305, 651 (2004).
[13]
C. D. Martin, S. M. Antao, P. J. Chupas, P. L. Lee, S. D. Shastri, and J. B. Parise, Applied Physics Letters 86(2005).
[14]
M. Inui, X. Hong, and K. Tamura, Physical Review B 68, 094108 (2003).
[15]
X. Hong and M. Newville, physica status solidi (b), 2000052 (2020).

RO6

Thu. 8, Sep. 22:10-22:30 JST
15:10-15:30 CEST

The structure of bismuth oxide glasses
Katsuki Hayashi1, Tatsuki Shimizu1, *Akira Saitoh1
1

Graduate School of Science and Engineering, Ehime University, Matsuyama, Ehime 790-8577, Japan
asaito@ehime-u.ac.jp
Keywords: Oxide glasses, Structure, Optical properties.

*

Functional oxide glasses are one of the key materials in our life. For example, lead oxide glasses providing highrefractive index have been applied to optical glass devices 1). But the toxicity elements including PbO are restrictedin the optical devices, nevertheless the ns2-type ions (Sn2+, Sb3+, Pb2+, and Bi3+) with high electron polarizability
being effective. We have reported a non-toxic oxide glass being high refractive index over 2.0 and very small
photoelastic constant less than 0.05×10–12 Pa–1 by choosing Bi3+ ion 2, 3).
The sesquioxide Bi2O3 in oxide glasses lead large ion-filling structure constituted by octahedral BiO6 units by
micro-Raman spectroscopy. However, no direct evidence regarding the valence of bismuth ions and the short- andmedium-range structures had not been elucidated. Thus, we report the valance state of bismuth ions elucidated by
HAXPES and XANES (Bi LIII-edge) and anionic structure about silicate, borate, and phosphate glasses networkby 29Si, 11B, and 31P MAS-NMR spectra and EXAFS.
Fig. 1 shows EXAFS spectra of the (a) NaBiO3, (b) Bi2O3, (c)57Bi2O3–43SiO2, (d) 55Bi2O3–45B2O3, and (e) 40Bi2O3–60P2O5
glasses. The first coordination manners of a Bi3+ ion in (c) and (d) arealmost the same of the crystalline Bi2O3. On the other hand, the secondnearest coordination in phosphate glass (e) is slightly shorted comparedwith that of crystalline Bi2O3. In short, there are four oxygens that
position at ~0.28 nm from a Bi3+ ion. These structures relate to opticalproperties such as light absorption and photoelasticity.
References
1) K. Kurosawa, Photonic Sensors 4, 12 (2014).
2) A. Saitoh, K. Hayashi, K. Hanzawa, S. Ueda, S. Kawachi, J.
Yamaura, K. Ide, J. Kim, G. Tricot, S. Matsuishi, K. Mitsui, T.
Shimizu, M. Mori, H. Hosono, and H. Hiramatsu, J. Non-Cryst. Solids
560, 120720 (2021).
3) K. Hayashi, T. Shimizu, S. Matsuishi, H. Hiramatsu, and A. Saitoh,J. Mater. Sci.: Mater. Electron. 33, 2242 (2022).
#

Present address: Graduate School of Science and Engineering, Ehime
University, Matsuyama, Ehime 790-8577, Japan.

Fig. 1. EXAFS spectra of (a) NaBiO3, (b) Bi2O3,(c) 57Bi2O3–43SiO2, (d) 55Bi2O3–45B2O3, and(e) 40Bi2O3–60P2O5 glasses.

RO7

Thu. 8, Sep. 22:40-23:00 JST
15:40-16:00 CEST

Atomic structure of bulk metallic glasses studied by transmission electron
microscopy, synchrotron-radiation X-ray diffraction, scanning tunnelingmicroscopy and ab-initio molecular dynamics simulation*

D. V. Louzguine1,2

1

MathAM-OIL, National Institute of Advanced Industrial Science and Technology (AIST), Sendai 980-8577,
Japan
2
Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Aoba-Ku, Sendai 980-8577,
Japan,*

dml@wpi-aimr.tohoku.ac.jp
Keywords (Maximum: 6 keywords, Minimum: 3 keywords, 10 point): X-ray scattering, Scanning tunnelingmicroscopy, Ab initio simulation.
Structural changes in a relatively strong Zr-Cu-Ni-Al bulk glass-forming liquid alloy on cooling from above
the equilibrium liquidus temperature were studied in-situ by synchrotron radiation X-ray diffraction andsupported by the results of first-principles molecular dynamics (MD) simulation. The results are also comparedwith those of a relatively fragile Pd-Cu-Ni-P liquid alloy, studied earlier. According to the pair distributionfunctions (PDF(R)) obtained chemical ordering forming extra Zr-Cu,Ni, Zr-Al and Zr-Zr atomic pairs takes
place in the Zr-Cu-Ni-Al supercooled liquid alloy on cooling towards the glass-transition temperature (Tg) [1].
However, here the change in the ratio of Zr-Cu,Ni atomic peak area to other peaks area in the first coordination
shell (Fig. 1a) is smaller than that found in case of the Pd-Cu-Ni-P alloy (Cu,Ni-P to other peaks ratio) in
accordance with a lower fragility index m=dlog()/d(Tg/T) (where  is the viscosity) of the Zr-Cu-Ni-Al melt.
Atomic redistribution between the first and second coordination shells is also observed. These findings indicatethat fragility is a sign of instability of short and medium range order in fragile liquids. These results will becompared with those of other research groups.
Also, the atomic structure of a Ni-Nb bulk metallic glass was directly resolved (Fig. 1b) by means of ultrahigh vacuum scanning tunneling microscopy (STM). Owing to the complicated electronic structure of the Ni-Nb
glassy alloy it also acts as a spectroscopy giving a chance to resolve local chemistry. STM allows detection of Ni
and Nb atomic positions separately depending on the applied potential. Direct atomic structure observation was
supported by MD simulation [2].
The structure of these and other bulk metallic glasses was also studied by high-resolution transmission
electron microscopy. New results will be presented.

(b)(a)
Figure 1. (a) Three typical PDF(R) (g(R)) functions of the Zr55Cu30Ni5Al10 glass-forming alloy upon in-situ
vitrification experiment on cooling. (b) An atomic structure of the Ni63.5Nb36.5 glassy alloy (STM).
References:
1) D.V. LOUZGUINE-LUZGIN, K. GEORGARAKIS, J. ANDRIEUX, L. HENNET, T. MORISHITA, K.
NISHIO, R.V. BELOSLUDOV, Intermetallics, 122, 106795, (2020).
2) R.V. BELOSLUDOV, A.I. ORESHKIN, S.I. ORESHKIN, D.A. MUZYCHENKO, H. KATO, D.V.
LOUZGUINE-LUZGIN, Journal of Alloys and Compounds, 816, 152680, (2020).

RO8

Thu. 8, Sep. 23:00-23:20 JST
16:00-16:20 CEST

Short range order controlling the atomic dynamics in metallic glasses*

X.D.Wang1, T.D. Xu1, K.K Qiu1, S.F. Wei1, Q.P. Cao1, D. X. Zhang2, J.Z. Jiang1

1

International Center for New-Structured Materials (ICNSM), Laboratory of New-Structured Materials, StateKey Laboratory of Silicon Materials, and School of Materials Science and Engineering, Zhejiang University,
Hangzhou, 310027, People’s Republic of China
2State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou, 310027, People’s
Republic of China*
wangxd@zju.edu.cn
Keywords (Maximum: Metallic glasses, X-ray absorption fine structure, Short range order, Atomic dynamics,
Ab initio simulation.
The secondary β-relaxation is an intrinsic feature in glassy materials. However, its structural origin is still not
well understood. Here we report that the β-relaxations in metallic glasses (MGs) mainly depend on the vibrationof small atoms, not only related to their surrounding local geometry but also chemical constitutions, i.e., theshort-range order. For examples, by using advanced synchrotron x-ray techniques and theoretical calculations,
we find that the tricapped-trigonal-prism-like polyhedra with more large La atoms in shells favor the local
vibration of center Ni atoms, leading to the pronounced β-relaxation event in La50Al15Ni35 MG [1]. In contrast,
Cu atoms are relatively close-packed with some Cu in the nearest neighbors while they could easily diffuse outof the cages compared to Ni, somehow triggering the onset of α-relaxation in La50Al15Cu35 MG. When focusing
on the as-cast and annealed La50Al15Ni35 MGs[2], we demonstrate that the chemical constitution around mobile
Ni atoms in Ni-centered polyhedra tends to transform from Al-free to Al/Ni-containing with decreasing the free
after annealing, suppressing the local vibration of central Ni atoms and thus leading to the unpronounced
β-relaxation event. Moreover, the atomic mobility of Ni atoms more depends on their local polyhedral geometry
and chemical constitution than the content of surrounding free volume. Despite the same composition andsimilar atomic sizes of Ni and Fe atoms, the β-relaxation in Y60Ni16Al24 and Y60Fe16Al24 MGs mainly depends onthe vibration of small Ni and Fe atoms, respectively [3]. From the x-ray absorption fine structure and Voronoi
tessellation statistics, it is found that the dominant local structure of mobile atoms changes from <0, 3, 6, 0>
centered by Ni atoms into <0, 2, 8, 0> centered by Fe atoms. More large Y atoms in shells promote the local
vibration of center Ni atoms. In contrast, with more Y atoms replaced by Fe atoms, the vibration of center Fe
atoms gets significantly slow down, thus leading to an unpronounced β relaxation. Our results provide an idea
for understanding the structural origin of β-relaxation behaviors in MGs and other glassy materials from theirlocal atomic environments and dynamics point of view.
References[1] X.D. Wang, J. Zhang, T.D. Xu, Q. Yu, Q.P. Cao, D.X. Zhang, J.Z. Jiang, J. Phys. Chem. Lett. 9, 4308(2018).
[2] K.K. Qiu, X.D. Wang, T.D. Xu, J. Liu, Q.P. Cao, D.X. Zhang, J.Z. Jiang, Mater. Today Phys. 21, 100515(2021).
[3] S.F. Wei, X.D. Wang, K.K Qiu, T.D. Xu, Q.P. Cao, S.Q. Ding, D.X. Zhang, J.Z. Jiang, Phys. Rev. B 105,
054313 (2022).

RO9

Thu. 8, Sep. 23:20-23:40 JST
16:20-16:40 CESTON THE RELATIONSHIP BETWEEN STRUCTURAL STATE,MECHANICAL PROPERTIES AND WEAR RESISTANCE OF A CUBASED BULK METALLIC GLASS.
*P. Laffont1, R. Daudin1, JJ. Blandin1, A. Lenain2, S. Gravier2, S. Stoens3, G. Colas3, P.H.
Cornuault3
1

Univ. Grenoble Alpes, SIMaP, Grenoble, F-38000, France, 2Vulkam Inc. Amorphous metal micro casting /www.vulkam.com / Gières, 38610, France, 3Univ. Bourgogne Franche-Comté FEMTO-ST Institute
CNRS/UFC/ENSMM/UTBM, Département de Mécanique Appliquée, Besançon, 25000, France*paul.laffont@grenoble-inp.fr
Keywords: Metallic glasses, alloying, relaxation, mechanical properties, wear resistance,
By quenching a liquid metallic alloy, the crystallization process can be bypassed to obtain an amorphous metal
called metallic glass. This class of metallic materials exhibits very high mechanical properties (high yield stress,
high hardness, large elastic strain) perfectly suitable for applications in micro-mechanics (such as micro-gears
for example) [1]. However, in this kind of application, the life time of the metallic glass object is directly related
to the its wear resistance which is not clearly understood up to date depending on the contact conditions as wellas the mechanical properties of both the metallic glasses and the counterpart. For most of the crystalline metallic
alloys, the Archard’s law directly correlates the wear resistance with the hardness of the material: the harder the
better. This law does not always apply for metallic glasses [2] suggesting that the difference in the local
deformation mechanisms (shear bands VS dislocations) can play an important role in predicting the tribologicalbehaviour of amorphous metals.
In the case of metallic glasses, the nucleation of shear bands is related to the hardness but their propagation isrelated to the plasticity. This work aims to propose a correlation between the wear resistance and the hardness aswell as plasticity. To do so, three strategies are performed to modify the hardness and/or plasticity of a Cu-based
BMG (Cu47Zr46Al7, at%): the addition of Nb, the relaxation of the excess free volume and the partial
crystallization of the alloy (see Figure). Each strategy is evaluated by micro-indentation as well as three points
bending. Moreover, using the results of numerous micro-scratch tests analysed by optical interferometricprofilometry, we will show the impact of these different strategies on the wear resistance, both on the wear rate
and the friction coefficient. Specific structural analyses along the wear tracks also show the development ofdifferent shear bands patterns depending on the chosen strategy revealing the importance of the hardness and/or
plasticity.

Fig. 1. Hardness and plastic deformation in function of the different treatments

RPL1

Plenary

Fri. 9, Sep. 16:00-16:40 JST
9:00-9:40 CEST

Behaviors of disordered alloys under high temperature and pressure*

Jian-Zhong Jiang 1, X.D. Wang1, Q.P. Cao1 and D.Z. Zhang1

1

International Center for New-Structured Materials (ICNSM), School of Materials Science & Engineering,
Zhejiang University, Hangzhou, P.R. China
jiangjz@zju.edu.cn
Keywords: Amorphous alloys, Metallic liquids, Temperature and pressure, X-ray scattering, MDs.
Phase transitions in materials are the subject of great interest. The polyamorphic transition induced bytemperature and/or pressure, defined as a transition between two different disordered phases (without long range
translation and orientation symmetries and with the same composition) in disordered materials, e.g., liquids andamorphous materials, is often more complex as compared to the polymorphic transition in crystalline materials.
In this talk, we will survey behaviors of disordered alloys (metallic liquids and metallic glasses) under various
temperatures and pressures. Firstly, temperature-dependent atomic structure evolutions in various metallic
liquids (from pure element to multi-component systems) will be mentioned, esp. challenges and potential for
liquid-to-liquid transition in metallic liquids will be critically discussed. Secondly, pressure-induced phasetransformation in various metallic glasses will be further discussed. Finally, simultaneously temperature- andpressure-induced polyamorphic transitions in disordered materials will be presented.

RCW1

Corporate Webinar

Heraeus AMLOY Technologies –The transition from scientific innovation
high-performance application solutions

Fri. 9, Sep. 16:40-16:55 JST
9:40-9:55 CEST

toseriesproductionofDr. Hans-Jürgen Wachter1, *Mrs. Valeska Melde2
1

Global Head of Heraeus AMLOY, Karlstein am Main, 63791, Germany, 2 Head of Marketing & Sales, Karlsteinam Main, 63791, Germany*
valeska.melde@heraeus.com (Corresponding author identified by the superscript of *)Keywords: Amorphous alloys, Bulk Metallic Glasses, Injection Molding, 3D Printing, Medical Technology,
Robotics & Mechanics, Sensor Applications_
Whether due to their exceptional combination of high strength and high elasticity in use as spring elements or intransmission applications, or due to their high corrosion resistance and even biocompatibility as medical sensors
or long-term implants, amorphous alloys have been seen as a potential solution to many challenges in high-tech
applications since their discovery. However, the challenging production of components from amorphous alloys,
in a reproducible, high quality with as little post-processing as possible and in a cost-efficient way, has so far
inhibited the use of this promising class of materials.
Heraeus AMLOY Technologies has managed to overcome this limitation as a fully integrated contract
manufacturer along the value chain. With its own alloyed raw material range of amorphous alloys, AMLOY isable to mass-produce bulk metallic glass components reproducibly according to technical drawings using an
adapted injection molding process and the additive LPBF process. The general quality controls by means of CT
and optical measurement are also extended by application-related test rigs and thus the performance ofcomponents made of AMLOY alloys continues to be confirmed and improved.
Fig. 1: Mechanical performance of AMLOY alloys regarding strength and elasticity

In addition to the mechanical properties shown in Fig. 1, AMLOY has also succeeded in addressing markets andentering development partnerships that place high demands on material purity (medical technology),
reproducible dimensional accuracy (sensor technology) and long-term stable performance (robotics &mechanics). AMLOY's consulting and support in the development process of the components also plays adecisive role here, successfully contributing its expertise in materials and manufacturing processes to design
guidelines for improving component performance in the application environments.
In addition to the recent expansion of AMLOY’s machine park, with its own and independently manufactured
production equipment in injection molding, in the future, the use of AMLOY materials in near-net-shape
manufactured components is expected to solve specific challenges in medical technology, robotics and sensor
technology and improve performance, to continue to accelerate amorphous alloys from scientific innovation toan established manufacturing method.

RO10

Fri. 9, Sep. 16:55-17:15 JST
9:55-10:15 CEST

Large-scale density fluctuations during structural transition in metallic glass
forming liquid beyond medium range order*

F. Yang1, N. Neuber2, B. Adams2, L. Kreuzer1,3, L. Ruschel2, M. Blankenburg4, R. Busch2, A.
Meyer11

Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt, Cologne, 51170,
Germany,2
Lehrstuhl für metallische Werkstoffe, Universität des Saarlandes, Saarbrücken 66123, Germany,3
Heinz Maier-Leibnitz Zentrum (FRM II), TU München, Garching 85748, Germany,4
Deutsches Elektronen-Synchrotron (DESY, Hamburg 22607, Germany*
fan.yang@dlr.de
Keywords: Liquid-liquid transition, SAXS/WAXS, in-situ synchrotron diffraction.
Phase transformation between two disordered structures i.e., the so-called polyamorphism, is a long-standing
issue in the field of liquid and glass physics, still being intensively studied and debated. This kind of
liquid-liquid (LL) transition was first suggested to be present in water [1]. Meanwhile, indications of the
LL-transition have been found in oxide, semiconductor, and a number of metallic glass-forming melts [2-4],
pointing to a rather general phenomenon. It has been proposed that such transitions can be interpreted as
analogous to an order-disorder transition, with a diverging correlation length at the transition point and a lambda
shaped heat capacity [2]. This scenario implies large impacts on the structural and dynamic properties of the melt,
including diffusion or liquid viscosity, as well as the glass forming ability (GFA). However, the physical natureand microscopic mechanism of the LL-transition is still not well understood. For oxide and molecular liquids,
the microscopic mechanism of the LL-transition can be often viewed structurally as a change of the bonding
angle or the coordination of the structural units. Classical metallic bonding is, on the other hand, nondirectional.
Thus, so far, changes of the medium-range order are considered to be relevant for the LL-transition in alloy melts[2,3]. Whether and how the observed LL-transition in metallic glass-forming liquids can be understood in
accordance with the general picture together with other glass formers is still not clear.
Only recently, direct structural investigations on two well-known bulk metallic glass forming liquids,
Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 and Zr58.5Cu15.6Ni12.8Al10.3Nb2.8, show that the kinetics of the LL-transition are rather
slow, which must involve long range, diffusion like mass transports [4]. Using a simultaneous SAXS/WAXS
setup, combined with electrostatic levitation, we are now able to investigate in-situ structural changes in theundercooled liquid across the liquid-liquid transition region on a length scale well beyond the medium rangeorder. We confirm the previous estimation of the occurrence of large-scale structural fluctuations on the order ofnanometers close to the transition temperature. Depending on the temperature of the undercooled melt, such
structural changes also act as a “precursor” of the crystallization of the undercooled liquid. The observed
characteristic length scale is incompatible with a transition mechanism involving local structural changes only, as
in the case of oxides or molecular liquids.
References:[1] C. A. Angell, Science 319, 582 (2008).
[2] S. Wei, F. Yang, J. Bednarčík, I. Kaban, O. Shuleshova, A. Meyer, and R. Busch, Nature Comm. 4, 2083
(2013).
[3] M. Stolpe, I. Jonas, S. Wei, Z. Evenson, W. Hembree, F. Yang, A. Meyer, and R. Busch, Phys. Rev. B 93,
014201 (2016).
[4] I. Jonas, F. Yang, A. Meyer, Phys. Rev. Lett. 123, 055502 (2019).

RO11

Fri. 9, Sep. 20:00-20:20 JST
13:00-13:20 CEST

Structure and dynamics in the no-man’s land of phase-change materials*

Shuai Wei

Department of Chemistry, Aarhus University, Aarhus, Denmark*shuai.wei@chem.au.dk
Keywords: phase-change materials, liquid-liquid transition, fragile-strong transition, metal-semiconductortransitions, X-ray/Neutron scattering, crystallizations.

Phase-change materials such as Ge-Sb-Te and Ge-Sb can be reversibly switched between amorphous andcrystalline states within the timescale of nanoseconds. The switchable states can be used to encode information
for data storage applications. While fast-switching rewritable nonvolatile memory units based on phase-changematerials are promising technologies for future computer memory devices, an in-depth understanding of thephysical factors that determine their success is still lacking(1, 2). Here we show the existence of a liquid-state
metal-to-semiconductor transition, located not far below the melting point, Tm, as essential(1, 3–5). The
metal-to-semiconductor transition is itself a consequence of atomic rearrangements that are involved in ahigh-density to low-density liquid-liquid transition and a fragile-to-strong transition in liquid viscosity. The latter
controls both the speed of crystallization and thestabilization of the glass state(6), which areessential for the understanding of materials’switching
behaviors.
Furthermore,wedemonstrate the direct structural evidence ofsuch a liquid-liquid transition in the supercooled
liquid state (no-man’s land) of phase-changematerials using femtosecond X-ray diffractions
with X-ray free electron lasers. At last, we
introduce a new parameter, the “metallicity”.
When Tm-scaled temperatures of known
metal-to-semiconductor transitions of Group IV,
V, and VI alloys are plotted against their
metallicities, the curvilinear plot leads directly tothe composition zone of all known phase-changematerials and the temperature interval below Tm,
which may provide guidance for tailoring thematerials(1)References
1.
2.
3.

4.
5.
6.

Fig. 1. Angell-plot of alloys based on group-VI, V,V. The
double kink in the Adam-Gibbs fitting curve (red curve)
reveals a fragile-strong transition. Taken from Ref.1.

S. Wei, P. Lucas, C. A. Angell, Phase-change materials: The view from the liquid phase and the metallicity
parameter. MRS Bulletin. 44, 691–698 (2019).
M. Wuttig, N. Yamada, Phase-change materials for rewriteable data storage. Nature Materials. 6, 824–32(2007).
P. Zalden, F. Quirin, M. Schumacher, J. Siegel, S. Wei, A. Koc, M. Nicoul, M. Trigo, P. Andreasson, H.
Enquist, M. J. Shu, T. Pardini, M. Chollet, D. Zhu, H. Lemke, I. Ronneberger, J. Larsson, A. M. Lindenberg,
H. E. Fischer, S. Hau-Riege, D. A. Reis, R. Mazzarello, M. Wuttig, K. Sokolowski-Tinten, Femtosecond
x-ray diffraction reveals a liquid–liquid phase transition in phase-change materials. Science. 364,
1062–1067 (2019).
S. Wei, Z. Evenson, M. Stolpe, P. Lucas, C. A. Angell, Breakdown of the Stokes-Einstein relation above themelting temperature in a liquid phase-change material. Science Advances. 4, eaat8632 (2018).
S. Wei, G. J. Coleman, P. Lucas, C. A. Angell, Glass Transitions, Semiconductor-Metal Transitions, andFragilities in Ge-V-Te (V=As, Sb) Liquid Alloys: The Difference One Element Can Make. Phys. Rev.
Applied. 7, 034035 (2017).
S. Wei, P. Lucas, C. A. Angell, Phase change alloy viscosities down to Tg using Adam-Gibbs-equation
fittings to excess entropy data: A fragile-to-strong transition. J. Appl. Phys. 118, 034903 (2015).

RO12

Fri. 9, Sep. 20:20-20:40 JST
13:20-13:40 CEST

Thermoplastic forming capacity of a ZrCoAl metallic glass for surface
patterning*Loïcia Gaudilliere, Rémi Daudin, Jean-Jacques Blandin

Univ. Grenoble Alpes, SIMaP, Grenoble, F-38000, France*
loicia.gaudilliere@grenoble-inp.fr
Keywords: thermoplastic forming, surface patterning, ZrCoAl, crystallization, high temperature rheology
Metallic glasses (MG) are known for their great properties at room temperature (hardness, yield stress, elasticstrain…) but are also interesting for their ability to be shaped at high temperature by thermoplastic forming(TPF) and surface patterning. Many studies were performed on precious MG such as Au-, Pd- or Pt-based
compositions and due to their oxidation resistance, TPF can be done under air1. Some Zr-based alloys are also
reported for TPF, because of the existence of a supercooled liquid region (SLR) usually associated with
Newtonian rheologies2,3.
In the present work, the Zr56Co28Al16 MG was chosen for its great potential for medical applications thanks to its
good compromise between corrosion resistance and mechanical behaviour4. This work focuses on the hightemperature rheology of this alloy with an emphasis concerning its thermal stability and the structuraltransformation processes occurring in the temperature range of the TPF window. Differential Scanning
Calorimetry (DSC) (Fig. 1) reveals a limited SLR (leading to a lack of Newtonian regime and suggesting
non-ideal conditions regarding TPF) and a two-stage crystallization behavior. Both X-Ray Diffraction andTransmission Electron Microscopy suggest that crystallization actually happens only around the second
exothermal peak. Compression tests including strain rate jumps at different temperatures were performed andshowed that an increase of the strain rate and/or the temperature may enhance the phase transformation kinetic.
Finally, despite relatively high viscosities and a lack of Newtonian regime (resulting from the associatedstructural transformations), surface patternings were successfully performed.

Fig. 1: DSC curve of the Zr56Co28Al16 metallic glass

References
1. Hasan, M. et al., Functionalization of Metallic Glasses through Hierarchical Patterning. Nano Lett. 15,
963–968 (2015).
2. Li, N. et al. A thermoplastic forming map of a Zr-based bulk metallic glass. Acta Mater. 61, 1921–1931(2013).
3. He, J. J. et al. The precision replication of a microchannel mould by hot-embossing a Zr-based bulk metallic
glass. Intermetallics 21, 50–55 (2012).
4. Guérin, E. Processing and properties of Zr-Co-Al bulk metallic glass for biomedical applications, Ph.D. Univ.
Grenoble Alpes (2022).

RO13

Fri. 9, Sep. 20:40-21:00 JST
13:40-14:00 CEST

Shape memory effect in metallic glasses*

Tianding Xu1, Xiao-Dong Wang2, Jian-Zhong Jiang3

1

International Center for New-Structured Materials (ICNSM), Laboratory of New-Structured Materials, StateKey Laboratory of Silicon Materials, and School of Materials Science and Engineering, Zhejiang University,
Hangzhou, 310027, China.
*
xutd@zju.edu.cn
Keywords: atomic dynamics, metallic glass, X-ray photon correlation spectroscopy, shape memory effect.
Shape memory effect (SME), mainly present in crystalline Ti-Ni alloys, is basically missing in metallic
glasses (MGs) that lack the long-range periodic order to characterize crystals. Here we report experimental
results of SME in annealed MGs, in which the low-energy configuration state recovery is observed by bothdifferential scanning calorimetry and X-ray photon correlation spectroscopy. We elucidate the origin of SME in
MGs under the potential energy landscape framework, i.e., after annealing, the energy of MGs enters into a deep
basin and atoms are located in the low-energy configuration state. Albeit deviating from their relative stableconfigurations by temperature changes, atoms in the annealed MGs tend to return to the low-energy atomic
configurations along certain trajectories as pre-annealing temperature is approached. These results could extend
the application of MGs as functional materials by directionally manipulating their energy states via annealing
and rejuvenation.
References:
1) T. D. Xu, X. Wang and J. Jiang, Matter , 4 (2021): 3327.
#
Present address: Zhejiang University, Hangzhou, 310027, China

RO14Fri. 9, Sep. 21:10-21:30 JST
14:10-14:30 CEST

Role of Y content on glass-forming ability and soft magnetic properties of
Co-Y-B metallic glasses
S. Ma, *M. Yao, *W. Zhang
Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School ofMaterials Science and Engineering, Dalian University of Technology, Dalian, 116024, P.R.China*
yaoman@dlut.edu.cn (M. Yao), wzhang@dlut.edu.cn (W. Zhang).
Keywords: Co-based metallic glasses, glass-forming ability, soft magnetic property, ab initio molecular
dynamics simulations, local atomic structures.
Co-based metallic glasses (MGs) have attracted great attention due to their excellent soft magnetic properties
including high permeability, low coercivity (Hc), and near-zero magnetostriction, whereas the poor
glass-forming ability (GFA) severely limits their applications and development [1-2]. To improve the GFA of
Co-based MGs while maintaining superior soft magnetic properties, microalloying with appropriate elements isan effective method [3-4]. Recently, we found that the thermal stability and GFA of Co75B25 alloy are effectively
enhanced with minor Y addition, accompanied by the improvement of magnetic softness. However, the influencemechanisms of Y content on GFA and magnetic behaviors remain unclear. Therefore, we employed ab initio
molecular dynamics (AIMD) simulations and density functional theory (DFT) calculations to analyze therelationship between local atomic structures and properties.
The experimental results demonstrated that the addition of 3.5 at.% Y into Co75B25 alloy promotes theoccurrence of glass transition (Fig. 1 (a)), and enlarges critical thickness tc to 240 μm, lowers Hc to 1.5 A/m withsaturated magnetic flux density Bs of 0.73 T. By calculating the local atomic structures (pair distribution function,
coordination numbers, chemical short-range order, Voronoi polyhedron, structure factor, and the ratio of voids),
dynamic behavior, electronic structure, magnetic moment, and magnetic anisotropy energy (MAE), it is revealed
that the local atomic structures of Co-Y-B MGs are dominated by the B-centered prism units, and Y plays a vitalrole in the formation of the densely packed structures. The strongest chemical affinities between B-B, Co-Y, and
B-Y pairs in Co71.5Y3.5B25 alloy are the critical factor for enhancing GFA and magnetic softness (Fig. 1 (c)). In
addition, we proposed a method to estimate the MAE of MGs, and the changes of Hc can be interpreted from thechanges in MAE (Fig. 1 (b)). We expect that our findings will provide new insights into the mechanism of the
microstructure-induced improvement of GFA and soft magnetic properties for Co-based MGs.

Fig. 1. (a) The differential scanning calorimetry curve, (b) coercivity and magnetic anisotropy energy, and (c) the typical Voronoi polyhedronof Co75-xYxB25 (x = 0, 3.5, 5) MGs.

References:
1) A. Inoue, B.L. Shen, H. Koshiba, H. Kato and A.R. Yavari, Nat. Mater. 2 (2003) 661-663.
2) A.H. Taghvaei, M. Stoica, K.G. Prashanth and J. Eckert, Acta Mater. 61 (2013) 6609-6621.
3) G.Q. Guo, L. Yang, S.Y. Wu, Q.S. Zeng, C.J. Sun and Y.G.Wang, Mater. Des. 103 (2016) 308-314.
4) H.K. Kim, J.P. Ahn, B.J. Lee, K.W. Park and J.C. Lee, Acta Mater. 157 (2018) 209-217.

RO15

Fri. 9, Sep. 21:30-21:50 JST
14:30-14:50 CEST

Formation of a local structural order in the aluminum melt before
crystallization*V.B.Vorontsov.1, V.K.Pershin2

1.Ural State University of Railway transport (USURT), Ykaterinburg, 620079, Russia, 2. Ural State University ofRailway transport (USURT), Ykaterinburg, 620034, Russia, *metranpazh23-1@ya.ru *Abstracts
Acoustic emission (AE) has been experimentally investigated with a decrease in the temperature of the aluminum
melt in the temperature range of 860-660 °. A Fourier analysis of the amplitude-frequency spectrum of AE signals
in the frequency range of 20 -200 kHz was carried out; periodically repeating signals with maximum intensity
were established. It is assumed that the acoustic spectrum of signals is associated with structural rearrangementsin the melt and reflects the transition from disorder to local order in liquid aluminum in the form of clusters. At
the Table.1 presents the results of cluster modeling and compares the frequencies calculated theoretically with thefrequencies determined experimentally. Below is a cluster model when the melt is cooled from a temperature of
860 °.
Tabl.1 The experimentally and theoretically calculated frequencies of cluster elements.

Based on calculations frequency data, taken from the Table were used to build a cluster model.

Fig.1 Model of an Al melt cluster during melt cooling from a temperature of 860°С.
Based on the above, the concepts of the melt structure before crystallization as a partially ordered clusters discussed
Key words: Crystal structure, Melts, Gradient, Acoustic emission, Temperature.

RO16

Fri. 9, Sep. 21:50-22:10 JST
14:50-15:10 CEST

Development of metal-metalloid high-entropy bulk metallic glasses withultrahigh thermal stability and strength*

Yanhui Li1, Wei Zhang1

1School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China
yhli@dlut.edu.cn
Keywords: High-entropy bulk metallic glass, Thermal stability, Crystallization behavior, Mechanical properties.
*

High-entropy alloys (HEAs) or called multi-principal component alloys have gained increasing attention in
the field of advanced metallic materials over recent years due to their unique composition characteristic andexcellent properties. The HEAs with a glassy structure, known as high-entropy bulk metallic glasses(HE-BMGs), have also been synthesized in some specific alloy systems, which provide an approach to designnovel BMGs. We have successfully developed metal-metalloid type HE-BMGs in the alloy systems of
Fe-Co-Ni-(B, Si, P, C) and Fe-Ni-Cr-Mo-(P, C, B), which exhibit larger supercooled liquid region, higher
crystallization temperature (Tx), larger undercooling, and more sluggish crystallization process upon heating thanthe conventional metallic glasses in the same systems. In addition, the Fe-Co-Ni-(B, Si, P, C) andFe-Ni-Cr-Mo-(P, C, B) HE-BMGs exhibit good soft magnetic properties and excellent corrosion resistance inacids and NaCl solutions, respectively. Recently, we added an appropriate amount of refractory metal (RM) into
a FeCoNi(B, Si) alloy and synthesized new HE-BMGs with further enhanced glass-forming ability, thermal
stability, and strength. The FeCoNiRM(B, Si) HE-BMGs possess high Tx and fracture strength up to 867 K and
4.2 GPa, respectively, which are superior among the reported HE-BMGs (Fig. 1).

Fig. 1 Fracture strength versus crystallization temperature of FeCoNiRM(B, Si) and other typical HE-BMGs.

References:
1) T. Qi, Y. Li, A. Takeuchi, G. Xie, H. Miao, W. Zhang, Intermetallics 66, 8 (2015).
2) Y. Li, W. Zhang, T. Qi, J. Alloys Compd. 693, 25 (2017).
3) Y. Xu, Y. Li, Z. Zhu, W. Zhang, J. Non-cryst. Solids 487, 60 (2018).
4) Y. Li, S. Wang, X. Wang, M. Yin, W. Zhang, J. Mater. Sci. Technol. 43, 32 (2020).

RO18

Fri. 9, Sep. 22:20-22:40 JST
15:20-15:40 CEST

Change of collective dynamics in supercooled
glass-forming aluminium film*

Dmitrii Fleita*,1,2, Genri Norman1,2,3, Vasily Pisarev1,2,3

1

HSE University, Moscow, 101000, Russia
Joint Institute for High Temperatures of the Russian Academy of Sciences, Moscow, 125412, Russia
3
Moscow Institute of Physics and Technology, Dolgoprudny, 41701, Russia*
fleyta.du@phystech.edu
Keywords: molecular dynamics, metastable states, spatio-temporal correlations, vitrification.
2

The thermodynamic functions of substance do not undergo any drastic changes in the point of phasetransition, and despite its exceptional influence in some manner on the behavior of a substance, is not special forthem [1]. Widely known, that any phase can exist, at least as metastable, and on the other side of the transition
point; thermodynamic inequalities at this point are not violated within the relaxation time.
Preliminary analysis of metastable fluids [2] with use of the molecular dynamics simulations (MD) revealedfeatures in the region of phase transitions for specific two-particle motion correlators [2, 3], and promisingchange in described collective dynamics of particles in various models of particle interactions was found.
In this particular work, the temporal behavior of motion correlators observed in deep supercooled state ofaluminium film near glass-transition temperature [4, 5]. The analysis shows a change of dynamical structure(Fig.1a) till and during the relaxation processes of vitrification and gives vitrification temperature which
consistent with volumetric (Fig.1b) and other analysis methods [6].

(a)

(b)

Figure 1. Temperature dependence of correlator CC(T, τ) for different diagnostic radius (left) and volume of film(right) for pure aluminium film after overcooling with rate in interval 1012-1014 Ks-1. Both shows two transition
temperatures 610 and 520 K, which detach different metastable states of supercooled liquid aluminium film.
This work was supported by the grant of the President of Russian Federation (project No. 17-79-20391). The
authors acknowledge the JIHT RAS HPC and HSE University HPC Cluster ”cHARISMa”.
References:
1) L. Landau, E. Lifshitz, Statistical Physics (Course of Theoretical Physics Vol. 5) (Oxford:
Butterworth-Heinemann) (1980).
2) D. Fleita, V. Pisarev and G. Norman, JETP Lett. 109, p. 667 (2019)3) V. Voloshin, G. Malenkov and Yu. Naberukhin, J. Struct. Chem. 54, p. S233 (2013)4) D. Fleita, V. Pisarev and G. Norman, J. Phys.: Conf. Ser. 1147, p. 012015 (2019)5) D. Fleita, G. Norman and V. Pisarev, J. Phys.: Condens. Matter 32, p. 214009 (2020)6) E. Kirova, G. Norman and V. Pisarev, Computational Materials Science 172, p. 109367 (2020)

RO19

Fri. 9, Sep. 22:40-23:00 JST
15:40-16:00 CEST

Atomic transport properties of Bi1-xZnx segregating alloys
Fysol Ibna Abbas1,2 and G. M. Bhuiyan1*
12Department of Theoretical Physics, University of Dhaka, Dhaka-1000, Bangladesh
Department of electrical and electronic Engineering, City University, Dhaka-1216, Bangladesh

Abstract
Atomic transport properties namely the shear viscosity and diffusion coefficient for liquid Bi1-xZnx segregating alloys aretheoretically investigated using the Rice-Allnatt theory. The interioinc interaction is described by a widely used local
pseudopotential. Temperature dependent behaviour of the mentioned transport properties is also investigated. The overall
agreement of our theoretical results with the available experimental data is found to be good for the whole range ofconcentration. More interestingly, results clearly exhibit the segregating feature of bending of the viscosity profile near thecritical concentration.
*gbhuiyan@du.ac.bd
Keywords: Segregating alloys, Rice-Allnatt theory, shear viscosity, diffusion coefficient.

RIL4

InvitedMon. 12, Sep. 16:00-16:30 JST
9:00-9:30 CEST

High-Dimensional Neural Network Potentials
for Simulations of Complex Systems*

J. Behler1

1

Theoretische Chemie, Institut für Physikalische Chemie, Universität Göttingen, Göttingen, 37077, Germany
joerg.behler@uni-goettingen.de
Keywords: Atomistic Simulations, Machine Learning Potentials, Molecular Dynamics*

A lot of progress has been made in recent years in the development of machine learning potentials (MLPs)
for atomistic simulations1). While the first generation of MLPs relying on single feed-forward neural networks
has been restricted to small molecules with only a few degrees of freedom, the second generation extended theapplicability of MLPs to high-dimensional systems containing thousands of atoms by constructing the totalenergy as a sum of environment-dependent atomic energies. High-dimensional neural network potentials(HDNNP)2) have been the first example of a second-generation MLP, and to date HDNNPs have been applied tomany different types of systems. Long-range electrostatic interactions can be included in third-generation
HDNNPs employing environment-dependent charges3), but only recently limitations related to the underlying
locality approximation could be overcome by the introduction of fourth-generation HDNNPs4), which are able todescribe non-local charge transfer and multiple charge states using a global charge equilibration step.
In this talk, the basic concepts of the different generations of HDNNPs will be briefly summarized, followed
by a discussion of applications with a focus on solid-liquid interfaces. In particular, our recent work on thelithium intercalation compound LixMn2O4, which is used as positive electrode material in lithium batteries,
and its interface with water will be presented5,6).

References:
1) J. Behler, J. Chem. Phys. 145, 170901 (2016).
2) J. Behler and M. Parrinello, Phys. Rev. Lett. 98, 146401 (2007).
3) N. Artrith, T. Morawietz, and J. Behler, Phys. Rev. B 83, 153101 (2011).
4) T. W. Ko, J. A. Finkler, S. Goedecker and J. Behler, Nature Comm. 12, 398 (2021).
5) M. Eckhoff, F. Schönewald, M. Risch, C. A. Volkert, P. E. Blöchl, and J. Behler, Phys. Rev. B 102, 164107(2020).
6) M. Eckhoff and J. Behler, J. Chem. Phys. 155, 244703 (2021).

RIL5

InvitedMon. 12, Sep. 16:30-17:00 JST
9:30-10:00 CEST

Structural inheritance and machine learning for materials design: from study ofliquid to prediction crystals*

Nikolay Chtchelkatchev1*, Roman Ryltsev2,1

1

Vereshchagin Institute for High Pressure Physics, RAS, 108840 Moscow, Troitsk, Russia
Institute of Metallurgy, Ural Branch RAS, 620016 Ekaterinburg, Russia*
chtchelkatchev@hppi.troitsk.ru
Keywords: Neural networks, Structural inheritance, Ab initio simulation, Machine learning, Genetic algorithms,
Compositional transferability.
2

The use of machine learning is a new paradigm in modern computational materials science [1-2]. One of themost promising and widely accepted techniques is using ab initio reference data on energies, forces, and stresstensors to develop machine learning interatomic potentials (MLIPs) with a flexible functional form which caneffectively fit the potential energy surface of the particle system. This approach allows solving the principal
problems of ab initio simulations: the effects of ‘‘small size” and ‘‘short time”, associated with difficulties insimulating sufficiently large supercells at long enough computational times. MLIPs can provide nearly ab initio
accuracy with orders of magnitude less computational cost for systems composed of up to millions of particles.
One of the most challenging applications of MLIPs is design of new functional materials on top of classicalmolecular dynamics simulations. It requires developing accurate MLIPs, universal for ordered (crystal) anddisordered systems (melts, supercooled liquids, glasses) in wide temperature and concentration ranges. This is adifficult task for materials design when possible ordered structures are not known.
We have found that MLIPs for multicomponent metallic alloys trained only on disordered configurations canaccurately describe crystal structures even at low temperatures. Training MLIP on liquid configurations isstraightforward: using certain algorithm we generate disordered configurations and find energy, interatomic
forces and virials using DFT. Disordered systems require rather large supercells (we use 512 particle sells) that
include a number of possible local structural configurations. Sampling enough the configurational space one canbuild representative training dataset.
We address MLIPs for multicomponent metallic melts taking the ternary Al-Cu-Ni ones as a convenient
example [3]. It is shown that MLIP trained on liquid configurations demonstrates good compositionaltransferability, which extends far beyond compositional fluctuations in the training configurations. Using so
trained MLIP we can describe not only liquid, but find with ab initio accuracy all stable and low-lying
metastable crystal configurations of AlCuNi using a laptop and USPEX genetic algorithm. Fig.1 shows that
MLIP trained on liquid quite well reproduce DFT equation of states for a crystal. The results obtained open up
prospects for design multicomponent metallic alloys with MLIPs.

Figure 1. (Left) Ternary plot for Al-Cu-Ni system with the compositions included in the training dataset.
(Middle) Snapshot of AlCuNi melt with 512 particles in the cell. (Right) Energy-volume relation obtained for
Al2Cu2Ni crystal using MLIP (Dp2) trained on liquid configurations and AIMD DFT in VASP.
Support of Russian Science Foundation (#18-12-00438) is acknowledged.
References (Example: non-mandatory, 10 point):[1] J. Behler and M. Parrinello, Phys. Rev. Lett. 98, 146401 (2007).
[2] L. Zhang, D.-Y. Lin, H. Wang, R. Car, and W. E, Phys. Rev. Materials 3, 023804 (2019).
[3] R.E. Ryltsev and N.M. Chtchelkatchev, J. Mol. Liq. 349, 118181 (2022).

RIL6

InvitedMon. 12, Sep. 20:00-20:30 JST
13:00-13:30 CEST

Finite-temperature modeling of materials with first-principles accuracy
Michele Ceriotti
Institute of Materials, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerlandmichele.ceriotti@epfl.ch
When modeling materials and molecules at the atomic scale, achieving a realistic level of complexity andmaking quantitative predictions are usually conflicting goals. Data-driven techniques have made great strides
towards enabling simulations of materials in realistic conditions with uncompromising accuracy. In this talk I
will summarize the core concepts that have driven the extraordinarily fast progress of the field, discuss some of
the most promising modeling techniques that combine physics-inspired and data-driven paradigms, indicate themost pressing open challenges, and present several applications to semiconductors and to metallic systems.
References
1) N. Lopanitsyna, C. Ben Mahmoud, and M. Ceriotti, Phys. Rev. Materials 5(4), 043802 (2021).
2) G. Imbalzano and M. Ceriotti, Phys. Rev. Materials 5(6), 063804 (2021).
3) F. Musil, A. Grisafi, A. P. Bartók, C. Ortner, G. Csányi, and M. Ceriotti, "Physics-Inspired Structural
Representations for Molecules and Materials," Chem. Rev. 121(16), 9759–9815 (2021).

Mon. 12, Sep. 20:30-20:50 JST
13:30-13:50 CEST

RO20

Composition Dependence of Melting Temperature of Rb-Na Alloy
Using First-principles-based Thermodynamic Integration*

A. Irie, A. Koura, K. Shimamura, F. Shimojo#

Department of Physics of Kumamoto University, Kumamoto, 860-8555, Japan*brauner.nacht@gmail.com
Keywords: Phase transition, Alkali metals, Thermodynamic integration, Ab initio simulation, Machine learning.
The melting point of alkali metal alloys depends non-linearly on the composition, and shows a minimum at a
certain composition which is different for each combination of alkali metals [1]. For instance, it has been
experimentally reported that RbxNa1-x alloy has the lowest melting point around x = 0.8 [2]. Due to these
remarkable characteristics, alkali metal alloys have drawn attention for the application as high-performancecoolants [3]. The purpose of this study is to theoretically clarify the microscopic origin of the minimum melting
temperature, which is lower than those of simple substances. We have investigated the concentration dependenceof melting points by using thermodynamic integration (TI) based on the first-principles molecular dynamics(FPMD) simulations. A non-empirical simulation model with high precision can be achieved using FPMD, but it
is computationally demanding, making it difficult to apply FPMD to TI. Machine learning interatomic potentials(MLIP) obtained by training FPMD data with artificial neural networks have enough accuracy and low
computational cost, and, therefore, contribute to overcoming this cost problem.
We estimated the melting temperatures of RbxNa1-x at x = 0.0, 0.5, 0.8 and 1.0. The system consists of 128
atoms in total. Figure 1 shows the composition dependence of melting points of RbxNa1-x by numerical simulationand experiment [2] (black crosses). The red circles represent the results obtained by TI with MLIP based on FPMD
with Γ point for Brillouin-zone sampling. The calculated melting points of Rb0.5Na0.5 are much lower than theexperimental values. To take system-size effects into account, we performed FPMD simulations with 4k-point
sampling, which corresponds to an electronic state calculation with an eight times larger system than the Γ point.
The green squares represent the results of 4k-point sampling, and show that the melting temperatures of Na andRb0.5Na0.5 are 20 K [4] and 65 K higher than those of theΓ point, respectively. We consider that the size effect on
the melting temperature for the mixture is larger thanpure Na because Rb0.5Na0.5 consists of only 64 atoms ofeach atomic species. Figure 2 shows Helmholtz freeenergies of the solid (black squares) and liquid (bluecircles) phases of (a) Na and (b) Rb0.5Na0.5 as a functionof the number of sampling k points. In pure Na, both theHelmholtz free energies of the solid and liquid phases
decrease with increasing the number of k points from 1
to 4. In contrast, the Helmholtz free energy of the liquid
phase of Rb0.5Na0.5 is almost independent of the numberof sampling k points, while that of the solid phase has theFig. 1. Composition dependence of melting temperatures of
RbxNa1-x. The green squares and the red circles represent
same behavior as in pure Na. The k-point dependence ofmelting points sampling 4k and Γ points for Brillouin-zone
the Helmholtz free energy is mostly due to that ofintegration, respectively. The black crosses correspond topotential energy U, and the entropy S is nearly unrelated
experimental values [2].
to the number of k points. It is quite characteristic thatthe potential energy of Rb0.5Na0.5 in the liquid phaseremains unchanged when the number of k points
changes.
In the presentation, we will discuss the dependenceof physical quantities on the number of sampling k points
in detail.
References:[1] X. Ren, et al., Calphad 35, 446 (2011).
[2] J. R. Goates, et al., Trans. Faraday Soc. 66, 25 (1970).
[3] Y. Gao, et al., Front. Energy 8, 49 (2014).
[4] A. Irie, et al., J. Phys. Soc. Jpn. 90, 094603 (2021).
#
Present address: Department of Physics, Kumamoto
University 2-39-1 Kurokami, Chuo-ku, Kumamoto 8608555, Japan.

Fig. 2. The number dependence of k point sampling of (a) Naand (b) Rb0.5Na0.5. The black squares and the blue circles
correspond to solid and liquid phase, respectively.

Invited

RIL7

Mon. 12, Sep. 21:00-21:30 JST
14:00-14:30 CEST

Response of the Free Energy Landscape toTemperature Modulation and Aging*

Takashi Odagaki1,2

1

Kyushu University, Fukuoka, 819-0395, Japan, 2 Research Institute for Science Education, Inc., Kyoto, 6038346, Japan*t.odagaki@kb4.so-net.ne.jp

Keywords: Free energy landscape, Aging, Temperature modulation, Non-equilibrium system
The free-energy-landscape (FEL) approach is a theoretical frame work for non-equilibrium systems [1]. It
provides unified understanding of dynamic and thermodynamic properties of super-cooled liquids including
cooling-rate dependence of specific heat and time-temperature-transformation diagram, and it gives a solid
foundation of the trapping diffusion model of glass transition [2] and the Adam-Gibbs relation [3,4]. The FEL is
defined in the configurational space by the density function produced by fast motion of atoms and therefore
depends on temperature in contrast to the potential energy landscape. Expressing the response of the FEL to atemperature modulation by relaxation of the FEL, I investigate the waiting time dependence of aging in various
systems
Many non-equilibrium systems show a delayed response to a sudden perturbation and the delayed responseis represented by a relaxation function. I first classify the aging into two types: Type I when the apparent
relaxation time is always an increasing function of the waiting time tw and type II when the apparent relaxation
time can increase or decrease as a function of the waiting time tw. I show that (1) the relaxation of the FEL
manifests itself as type II aging and (2) the relaxation time of the FEL canbe deduced from the waiting time dependence of the apparent relaxationtime.
As examples, I first investigate the self-part of the intermediate
scattering function (FSKT) for a random walk model and show that thedelayed response of the FEL gives rise to type II aging. Figure 1 shows
the time dependence of FSKT for various values of tw when thetemperature is increased (T ↑) or decreased (T ↓) suddenly at time t = 0.
The relaxation time of FSKT is a decreasing function of tw for T-up
protocol and an increasing function of tw for T-down protocol which is notseen in the KWW relaxation.
Next, I investigate the relaxation function and the susceptibility of adielectric relaxation [5,6] and the massless Landau model under sudden
modification of temperature. On the basis of the two-time relaxation
Fig. 1 Time dependence of FSKT
function and the two-time instantaneous decay constant, I show that thefor different waiting times
aging in these systems belongs to type II aging when the free energy
when the temperature islandscape responds to the temperature change with a delay [7].
increased or decreased
suddenly at t=0.
References[1] T. Odagaki, J. Phys. Soc. Jpn. 86, 082001 (2017).
[2] T. Odagaki and Y. Hiwatari, Phys. Rev. A41, 929 (1990).
[3] G. Adam and J. H. Gibbs, J. Chem. Phys. 43, 139 (1965).
[4] T. Odagaki, J. Phys. Soc. Jpn. to appear (2022).
[5] K. Fukao and D. Tahara, Phys. Rev. E 80, 051802 (2009).
[6] T. Hecksher, N. B. Olsen, K. Niss, and J. C. Dyre, J. Chem. Phys. 133, 174514 (2010).
[7] T. Odagaki, Y. Saruyama and T. Ishida, J. Non-Cryst. Solids 558, 119448 (2021).

RIL8

InvitedMon. 12, Sep. 21:30-22:00 JST
14:30-15:00 CEST

New understanding of liquid thermodynamics, viscosity and its lower bounds
Kostya Trachenko
School of Physical and Chemical Sciences, Queen Mary University of London, United Kingdom
k.trachenko@qmul.ac.uk
Understanding most basic thermodynamic properties of the liquid state such as energy and heat capacity
turned out to be a long-standing problem in physics [1]. Landau&Lifshitz textbook states that no generalformulas can be derived for liquid thermodynamic functions because the interactions are both strong andsystem-specific. Phrased differently, liquids have no small parameter. Recent experimental and theoretical results
open a new way to understand liquid thermodynamics on the basis of collective modes (phonons) as is done in
the solid state theory. There are important differences between phonons in solids and liquids, and we haverecently started to understand and quantify this difference. I will review collective modes in liquids including
high-frequency solid-like transverse modes and will discuss how a gap in the reciprocal space emerges anddevelops in their spectrum [2,3]. This reduces the number of phonons with temperature, consistent with theexperimental decrease of constant-volume specific heat with temperature [1]. I will discuss the implication of theabove theory for fundamental understanding of liquids. I will also mention how this picture can be extended
above the critical point where the recently proposed Frenkel line on the phase diagram separates liquid-like andgas-like states of supercritical dynamics [1,4]. I will subsequently describe how this leads to the theory ofminimal quantum viscosity in terms of fundamental physical constants and will compare this minimum to theholographic bound [5]. The minimum of thermal diffusivity can be equally written as the same combination of
fundamental constants, in agreement with experiments. I also mention an upper bound on the speed of sound interms of fundamental constants following from a similar approach [6]. Finally, I will note that the kinematic
viscosity of the quark-gluon plasma is surprisingly close to the kinematic viscosity of liquids at their minimum[7].
References:[1] K Trachenko and V Brazhkin, Collective modes and thermodynamics of the liquid state, Reports on Progress
in Physics 79, 016502 (2016)[2] C Yang, M T Dove, V Brazhkin and K Trachenko, Physical Review Letters 118, 215502 (2017)[3] M Baggioli, M Vasin, V Brazhkin and K Trachenko, Physics Reports 865, 1 (2020)[4] C Cockrell, V Brazhkin and K Trachenko, Physics Reports 941, 1 (2021)[5] K Trachenko and V Brazhkin, Minimal quantum viscosity from fundamental physical constants, Science Adv.
6, eaba3747 (2020)[6] K Trachenko, B Monserrat, C Pickard and V Brazhkin, Science Adv. 6, eabc8662 (2020)[7] K Trachenko, V Brazhkin and M Baggioli, Similarity between the kinematic viscosity of quark-gluon plasma
and liquids at the viscosity minimum, SciPost Phys 10, 118 (2021)

RIL9

InvitedMon. 12, Sep. 22:10-22:40 JST
15:10-15:40 CEST

Thermodynamic and Structural Studies on Glass Transitions ofMolecular Glasses*

O. Yamamuro1, Y. Mizuno1, Y. Zhao1, H. Akiba1, S. Tatsumi2, S. Kohara3, K. Ohara4, Y.
Kono5, N. Kondo5, M. G. Tucker6, M. T. McDonnell6
1

Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan, 2 Faculty of Material
Science and Engineering, Kyoto Institute of Technology, Kyoto 606-8585, Japan, 3 Research Center for
Advanced Measurement and Characterization, National Institute for Materials Science (NIMS), Ibaraki
305-0047, Japan, 4 Diffraction and Scattering Division, Japan Synchrotron Radiation Research Institute (JASRI),
Hyogo 679-5198, Japan, 5 Geodynamic Research Center, Ehime University, Matsuyama 790-8577, Japan, 6
Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA*
yamamuro@issp.u-tokyo.ac.jp
Keywords: Glass, Liquid, Heat capacity, X-ray diffraction, Neutron diffraction, RMC modeling
Glass transition is one of the most important unsolved subjects in condensed matter physics. It is said that thehistory of the glass transition study started when Giauque found a heat capacity jump of glycerol in 1923 [1]. As
shown in this example, thermodynamic experiments, e.g., heat capacity, thermal expansivity, etc., are the mostdirect approach to investigate the glass transition. For the last 20 years, we have measured the heat capacities ofmany simple molecular liquids to investigate the structures of liquids and glasses through the configurational
entropy based on the Adam-Gibbs theory [2]. For very simple molecules, which crystallize readily on cooling,
we used vapor deposition (VD) method at low temperature (T < 10 K) whose speed is estimated to be more than
107 Ks-1. The VD procedure was performed by using an adiabatic calorimeter with which heat capacity wasmeasured in situ. We found that the cooperative rearranging regions (CRRs) of liquids increase on cooling,
especially below their melting temperatures, and reach 4-7 molecules at the glass transitions for many molecules
including carbon tetrachloride (CCl4), carbon disulphide (CS2), propane (CH3CH2CH3), and propene(CH3CH=CH2), which cannot be vitrified by usual liquid quenching [3,4].
Recently we are studying the short- and intermediate-range structure of simple molecular liquids and glasses
by using X-ray and neutron diffraction techniques [5-7]. The simplicity of molecular structure is more importantin diffraction works than in thermodynamic ones since the structure factor S(Q), which is Fourier transformationof the pair distribution function, cannot provide definite information on intermolecular correlations forcomplicated molecules with many intra- and intermolecular atomic pairs with close atomic distances. Hence, wehave constructed cryostats for both an in house X-ray diffractometer [5] and a high-energy X-ray diffractometer
at BL04B2, SPring-8 [6]. By using these instruments, we have succeeded in forming the glasses of carbon
dioxide, carbon disulphide, carbon tetrachloride, propane, propene, and toluene, and measured their X-ray
diffraction data in a wide Q range of 0.2 to 25 Å-1. Both CO2 and CS2 are rigid linear molecules while propane
and propene are dog-leg molecules and toluene is a planar molecule. The diffraction data of their liquid states
were also measured in a temperature range above their crystallization temperatures. Fig. 1 shows the reduced
pair distribution functions of liquid and glassy CS2 in a wide temperature range of 3-300 K. These data clearly
indicate that the intermolecular correlation becomes gradually larger on cooling and drastically sharpened at a
glassy state. On the basis of these data, we have performed molecular dynamics (MD) and reverse Monte Carlo(RMC) analyses. The results are quite consistent with the CRRs obtained by the thermodynamic works. In thepresentation, we are going to show very recent diffraction data under high pressure up to 5 GPa.
References
1) G. E. Gibson and W. F. Giauque, J. Am. Chem. Soc.
45, 93 (1923).
2) G. Adam and J. H. Gibbs, J. Chem. Phys. 43, 139(1965).
3) O. Yamamuro, et al., J. Phys. Chem. B, 102, 1605
(1998).
4) S. Tatsumi, S. Aso, O. Yamamuro, Phys. Rev. Lett.
109, 045701 (2012).
5) Y. Mizuno, M. Kofu, O. Yamamuro, J. Phys. Soc. Jpn.,
85, 124602 (2016).
6) Y. Mizuno, et al., J. Chem. Phys., 156, 034503 (2022).
7) O. Yamamuro, et al, Europhys. Lett., 63, 368 (2003).
Fig. 1. Reduced pair distribution functions of CS2

RO21

Mon. 12, Sep. 22:40-23:00 JST
15:40-16:00 CEST

On the thermodynamics and its connection to structure in the Pt-Pd-Cu-Ni-P
bulk metallic glass forming system*

Nico Neuber1, Oliver Gross1, Maximiliam Frey1, Benedikt Bochtler2, Alexander Kuball2,
Simon Hechler2, Isabella Gallino1, Ralf Busch1
1

Chair of Metallic Materials, Saarland University, Campus C6.3, Saarbrücken, 66123,Germany
Amorphous Metal Solution, Michellinstraße 9, Homburg, 66424, Germany (10 point)*nico.neuber@uni-saarland.de (Corresponding author identified by the superscript of *, 10 point)
Keywords: Thermodynamics, Fragility, Bulk metallic glass, Noble metal, Synchrotron X-ray diffraction,
Structural analysis
2

Contrary to basic hard sphere structure models, recent studies revealed, significant structural differences
between Pt-Cu-Ni-P and Pd-Cu-Ni-P metallic glass-forming liquids with the same stoichiometry. To cover the#(Pt/Pd)42.5Cu27N9.5P21. For this systematic set of alloys, the thermodynamic properties, such as isobaric heat
capacity, enthalpy and Gibbs free energy are assessed. A systematic drop of the Gibbs free energy difference
between crystal and liquid, providing a lower estimate of the driving force for crystallization was observed,
underlining the high glass-forming ability of the Pd-rich systems. Contrary to kinetic fragility data, a change ofthe thermodynamic fragility can be observed, drawing the picture of an increasing thermodynamically strong
behavior with rising Pd-content. Further, the temperature induced changes of the total structure factors S(Q)were monitored using high-energy synchrotron X-ray diffraction. Focus was laid on the changes on themedium-range length scale, by analyzing changes of the first sharp diffraction peak. Here a good correlation of
the changes in peak-width and the thermo- dynamic fragility was found. From the determination of the excess
enthalpy, large amounts of residual enthalpy in the glassy state were observed for the Pt-rich alloys, supporting
the increased ductility of these alloys. The current findings further carve out the different roles of the
topologically similar Pt and Pd in the Pt/Pd-Cu-Ni-P alloy system and how the change of the structural motifs on
the medium range order is influencing thermal properties such as enthalpy and heat capacity.

Figure 1: Graphical Abstract of the Talk: The structural changes, namely the changes of the width of the first sharp diffraction peak,correlate to the jump in specific heat capacity, used as a measure of the growth in configurational entropy in the liquid state during
deep undercooling of the melt.

Poster Presentations
Abstracts

P1
Determination of cooperatively rearranging regions in binary glass former*

Tomoko Mizuguchi1, Takashi Odagaki2

1

Faculty of Materials Science and Engineering, Kyoto Institute of Technology, Kyoto, 606-8585, Japan,
Research Institute for Science Education Inc., Kyoto, 603-8346, Japan*mizuguti@kit.ac.jp
Keywords: Cooperative rearranging regions, Configurational entropy, Molecular dynamics simulations, Glass,
Kob-Andersen model2

The dynamical slowing down in glassy system is attributed to the cooperative motion of particles. The AdamGibbs scenario is one of the theories focusing on the cooperative motion and can explain the divergence ofviscosity at finite temperatures of glassy materials in a phenomenological way [1,2]. The central idea of this theory
is to relate cooperatively rearranging regions (CRR) to configurational entropy. The CRR is defined as theminimum size of a space in which atoms can relax. The size of CRR has been determined in several ways, but
distributed depending on experiments [3]. In this study, we carried out molecular dynamics (MD) simulations todetermine the temperature dependence of CRR size and discuss the relationship between the CRR andconfigurational entropy.
We used Kob-Andersen Lennard-Jones (KALJ) model which has been widely used as a simple glass former of abinary alloy [4]. All simulations were performed using LAMMPS with a timestep of 0.005 in LJ units. The
isothermal-isochoric (NVT) conditions at a density of 1.2 were realized using the Nose-Hoover thermostat. To
determine the size of CRRs, we set up a space of spheres of various radii and fixed the atoms outside the spheres.
We changed the radius of sphere and determined the minimum size of sphere in which atoms cannot relax in a
sufficient time. Structural relaxation of atoms was observed by analyzing the bond break correlation [5]. The
method measures the bonds between particles at t=0 can survive after time or not. Fig.1 shows the number ofsurvival bonds at various radii of spheres at T=2.0 (normal liquid). As the radius decreases, the bonds are hard to
break. Fig.2 shows the temperature dependence of the number of survival bonds with the radius R=3.0. At the hightemperature of T=2.0, the number of bonds decreases rapidly. The rate of decrease becomes slow at T=1.0, but thebonds still breaks with time. At T=0.5, near the glass transition point, the bonds at t=0 hardly break after 500,000
timesteps, thus the number of bonds keeps the initial value. Namely, the atoms in the spherical area does not relax.
We will discuss the size of CRRs in relation to the configurational entropy.
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0

R=2.0
R=3.0
R=7.0

100000 200000 300000 400000 500000

t

Fig. 1. The number of survival bonds between
particles versus time at T=2.0 (normal liquid)
as the radius of a mobile space R is changed.

1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0

T=0.5
T=1.0
T=2.0

100000 200000 300000 400000 500000

t

Fig. 2. The number of survival bonds between
particles versus time at the radius of a mobile
space R=3.0 as the temperature is changed.

References:1) G. Adam and J. H. Gibbs, J. Chem. Phys. 43, 139 (1965).
2) T. Odagaki, J. Phys. Soc. Jpn. 91, 043602 (2022).
3) T. Kanaya, I. Tsukushi, K. Kaji, J. Bartos, and J. Kristiak, J. Phys. IV France 10, Pr7-317 (2000).
4) W. Kob and H. C. Andersen, Phys. Rev. E 51, 4626 (1995).
5) R. Yamamoto and A. Onuki, J. Phys. Soc. Jpn. 66, 2545 (1997).

P2
Novel Experimental Scheme for Microscopic Study of Johari-Goldstein Process*

Makina Saito1*, Yoshitaka Yoda2, Makoto Seto3,

1

Tohoku University, Sendai, 980-8578, Japan, 2 Japan Synchrotron Radiation Research Institute, Sayo, 679-5198,
Japan, 3 Kyoto University, Kumatori, 590-0494, Japan*makina.saito.d6@tohoku.ac.jp
Keywords: Synchrotron radiation, Quasi-elastic scattering, Johari-Goldstein process, Glass transition
The Johari-Goldstein-(JG) process is widely observed in a variety of glass-forming systems and recognized
as an intrinsic process in deeply supercooled and glassy states. In a deeply supercooled region, the JG process
starts to be observed as its time scale branches from the time scale of microscopic diffusion process (α process)by cooling. The JG process appears on the high-frequency (shorter time scale) side compared with the α process.
By further cooling, the temperature dependence of the JG relaxation time follows the Arrhenius law insupercooled state and even in glass state, where the α process almost freezes. Therefore, the JG process is often
one of the main origins of the structural relaxation in glass and known to be the microscopic origin of some glass
properties related to the structural relaxation such as stability of glass state and resistance for impact. Therefore,
understanding the mechanism of the JG process is highly useful to effectively improve these glass properties.
Some experimental techniques such as dielectric relaxation spectroscopy and NMR, which are often used to
study the JG process, have poor information on the spatial scale of the JG process. Here, inelastic andquasi-elastic scattering experiments allow us to determine the spatial scale of dynamics. In Fig. 1(A), we show
the typical time and spatial scale of the α process and the JG process. In Fig. 1(B), time and spatial scales
covered by some established inelastic and quasi-elastic scattering techniques such as inelastic X-ray scattering(IXS), quasi-elastic neutron scattering (QENS), neutron spin echo (NSE) techniques, are shown. As shown in the
figures, the JG process is difficult to be directly observed by the conventional techniques. In addition to theexperimental difficulty, the JG process is quite difficult to be observed by MD simulation because of its
relatively slow time scale. Therefore, the microscopic picture of the JG process is largely uncertain.
Quasi-elastic gamma-ray scattering spectroscopy (QEGS) using multi-line Mössbauer time-domaininterferometry (TDI) based on synchrotron radiation has been recently developed to the application level in
SPring-8.1) Using this technique, microscopic motions can be observed by measuring intermediate scatteringfunction in appropriate momentum-transfer (q) ranges corresponding to angstrom scales and in the time scales
between nanosecond to sub-microsecond.1,2) As shown in Fig. 1(A) and 1(B), TDI-based QEGS is very suitablefor direct observation of the JG process because the method can access to the atomic/molecular scale dynamics
in the time scale of 100 nanosecond, where the JG processes dominate the relaxations.
The JG process has not been observed in small molecular glass-forming systems by the conventional inelastic
and quasi-elastic scattering techniques. Previously, we succeeded to observe the JG process in small moleculesfor o-terphenyl by using TDI-based QEGS.3) In addition, we found the anomalous q dependence of the relaxation
time of the intermediate scattering function whose relaxation is caused by the JG process.3) TDI-based QEGS
was also applied to polymeric glass former polybutadiene and the JG process was microscopically observed inpolybutadiene.4) Very recently, the JG process was revealed in glycerol, where the JG process has not beenclearly observed by any methods, by using TDI-based QEGS.5) There results suggest that the JG process exists invariety of glass forming systems and TDI-based QEGS is ideal tool to investigate the JG process.
We introduce summary of the studies on the JG process and recent upgrade of the TDI-QEGS experimental
system at BL35XU. In addition, we discuss the new experimental scheme to directly reveal the microscopic
behaviour of the JG process based on the experimental data such as the temperature and q dependences of therelaxation time obtained by using TDI-QEGS.
References:1) M. Saito, R. Masuda, Y. Yoda, M. Seto, Sci. Rep. 7,12558 (2017).
2) A. Q. R. Baron, H. Franz, A. Meyer, R. Rüffer, A. I.
Chumakov, E. Burkel, W. Petry, Phys. Rev. Lett. 79,
2823 (1997).
3) M. Saito, S. Kitao, Y. Kobayashi, M. Kurokuzu, Y.
Yoda, M. Seto, Phys. Rev. Lett. 109, 115705 (2012).
4) T. Kanaya, R. Inoue, M. Saito, M. Seto, Y. Yoda, J.
Chem. Phys. 140, 144906 (2014).
5) M. Saito, M. Kurokuzu, Y. Yoda, and Makoto M.
Seto, Phys. Rev. E 105, L012605 (2022).

Fig. 1. (A) typical time and spatial scale of the diffusion process (αprocess) and the JG process. (B) time and spatial scales covered bysome experimental techniques.

P3
Configurational entropy of an isotropic monatomic glass
A. Ueno1 and *T. Mizuguchi2
1

Graduate School of Science and Technology, Kyoto Institute of Technology, Kyoto, 606-8585, Japan
Faculty of Materials Science and Engineering, Kyoto Institute of Technology, Kyoto, 606-8585, Japan*mizuguti@kit.ac.jp
Keywords: Glass transition, Configurational entropy, Reversible scaling method, Adiabatic switching process,Lennard-Jones-Gauss potential
2

The glass transition is one of the major unsolved problems in condensed matter physics. A theoreticalframework that can explain the glass transition in a unified manner does not yet exist, and various theories are
currently being proposed. One of the most promising candidates is the theory based on the configurational entropy,
which is the entropy corresponding to the number of atomic configurations. Various methods have been proposed
to estimate the configurational entropy in computer simulations. In general, it is not easy to calculate only theconfigurational entropy, since the total entropy is composed of multiple contributions including configurational,
mixing, harmonic vibrational, and non-harmonic vibrational components. Therefore, the relationship between theconfigurational entropy and the structure is still a central issue for the study of glass transition. To discuss thisrelationship quantitatively, we calculate the configurational entropy in simulations using a monatomic glassforming model where the atoms interact each other isotropically.
We performed molecular dynamics simulations using Lennard-Jones-Gauss (LJG) potential [1] (Fig. 1). The
general form of the effective two-body potential of alloys is an oscillatory potential consisting of a short-range
repulsion term and a damping oscillation (Friedel oscillation) term. The LJG potential can be regarded as the cutoffof such an oscillatory potential at the second maximum [2]. First, we quenched from the melt at T=2.5 to T=0.1
and obtained a glassy state. Fig. 2 shows the temperature dependence of the potential energy during heating fromthe glassy state at T=0.1. We obtained the configurational entropy by calculating the free energy over a wide rangeof temperatures. The configurational entropy is defined as the total entropy minus the vibrational entropy. The freeenergy of the glass at any temperature was obtained by the reversible scaling (RS) method [3] using the glass at atemperature T=0.1 as the reference system, and the derivative of this free energy with respect to temperature is
regarded as the vibrational entropy. The free energy of the liquid at any temperature was obtained by the RS methodwith the liquid at T=2.5 as the reference system, and the derivative of this free energy with respect to temperature
is considered as the total entropy. The free energies at T=0.1 (glass) and T=2.5 (liquid), which are the referencesin the RS method, can be obtained by adiabatic switching process [4] using the Einstein crystal and the UhlenbeckFord model, respectively.

Fig. 1. The shape of LJG potential. All quantities
are dimensionless in LJ units.

Fig. 2. Temperature Dependence of potential
energy that was obtained by heating at rate2 × 10!" step!# from T=0.1 to 2.5.

References:1) M. Engel, H. R. Trebin, Phys. Rev. Let. 98(22), 225505 (2007).
2) V. Van. Hoang, T. Odagaki, Physica B Condens. Matter 403(21-22), 3910-3915 (2008)3) M. de Koning, A. Antonelli, Phys. Rev. B 55(2), 735 (1997).
4) M.de Koning, A. Antonelli, S. Yip, Phys. Rev. Let. 83(20), 3973 (1999).

P4
Anomaly of Linear Thermal Expansion Coefficient induced by rejuvenation
treatment*

Tomoya OSHIKIRI1, Masato OHNUMA1, Motoki OHTA2, Rui YAMADA3, Junji SAIDA4

1

Hokkaido University, Sapporo, 060-8628, Japan, 2Shimane University, NEXTA, Matsue, 690-8504, Japan,
Tohoku University, IMR, Sendai, 980-8577, Japan, 4Tohoku University, FRIS, Sendai, 980-8578, Japan,*
ohnuma.masato@eng.hokudai.ac.jp
Keywords: Rejuvenation, Free Volume, Localized flow unit
3

Recently, we have shown that linear thermal expansion measurements using Thermo-Mechanical Analysis(TMA) can detect small length change due to the release of quenched-in strain even in the amorphous ribbons.
Analysing anomaly of Linear Thermal Expansion Coefficient (LTEC) can give us the relationship between themechanism of quenched-in strain and localized flow units1). Because LTEC is also sensitive to the volume change
due to release of free volume, we applied TMA measurements before and after rejuvenation treatments in asquenched and pre-treated Fe-Si-B amorphous ribbons. Sample
size for TMA measurements is 15mm x 5mm x 0.02mm. As
the rejuvenation treatments, samples are dipped into liquid
nitrogen for 10 seconds and following by dipping into warm
water for 10 seconds. These process were repeated 20 times
for the one set of the rejuvenation treatment. Figure 1 shows
the temperature dependence of LTEC with and without
rejuvenation process. One set of LTEC measurement consistsof four heating processes. The first one was the heating processwith the heating rate of 20 K/min up to 300ºC which is shownas black curves in the Fig.1. Then, the sample was cooled
down to 80ºC and again heated to 400ºC as the second heatingprocess which is shown by red curves. The difference between
black and red is caused by the release of free volume in thetemperature range below 300ºC. Then the sample was cooled
down again to 80ºC and then heated to 550ºC. Since theinflection point due to the invar effect of this alloy appears at
410ºC, it is difficult to discuss the free volume release above
this temperature. However, free volume release from 300 to
Fig.1 LTEC curves of Fe-Si-B as-quenched amorphousribbons measured along the ribbon direction (a) before
400ºC appears as the difference between green and red curves.
and (b) after the rejuvenation treatment. LTEC are
More than three times measurements have been performed toobtained from the linear thermal expansion rate measured
suppress the artifacts manly due to vibration and slipping.
by TMA with the heating rate of 20 K/min. The color ofComparing the LTEC behavior between the ribbons, clear
the curves represents the heating process; black (1stheating up to 300ºC, red: 2nd one up to 400ºC, green 3rd
enhancement of the free volume release in the sample with
one up to 550ºC. Those are the curves for amorphous
rejuvenation treatments appear as shown by the circles instate. Since the crystallization occurs by the 3rd heating,Fig.1. The effects of pre-treatment including annealing for
the LTEC curve for the fourth heating reperesent thereleasing quenched-in strain or cold rolling will also be
crystalline state. It shows relatively constant compare toother curves.
discussed in this presentation.
1) P.Kozikowski, M.Ohnuma, R.Hashimoto, K.Takano, G.Herzer, M.Kuhnt, C.Polak, Phys.Rev. Mater.,
4(2020), #095604

P5

The structural analysis of low-density liquid phosphorus
using reverse Monte Carlo simulation
Takuya Nishioka, Hiroki Naruta, *Kazuhiro Fuchizaki
Department of Physics, Ehime University, Matsuyama, 790-8577, Japan*fuchizak@phys.sci.ehime-u.ac.jp
Keywords: Liquid-liquid transition, Phosphorus, Reverse Monte Carlo simulation.
After the exciting discovery of phosphorus' liquid-liquid transition (LLT)1) at the beginning of this century,
many substances undergoing an LLT have been identified. However, like phosphorus, substances exhibiting atransition between thermodynamically stable phases are still rare. Under these circumstances, sulfur may
probably be a unique substance whose polyamorphic phase diagram, including the location of the (second)
critical point, was unveiled.2) Although phosphorus and sulfur are believed to transform from a molecular topolymerized liquid state on the pressure-induced LLT, the Clapeyron slope of phosphorus (sulfur) slope isnegative (positive). The quantitative entropy difference between the low-density liquid (LDL) and high-density
liquid (HDL) phases could explain the difference in the slope's sign. However, no structural analysis useable forthe entropy estimation has been done to the authors' knowledge. Here, we show for the first time thethree-dimensional atomic arrangement in phosphorus' LDL state with the help of reverse Monte Carlo (RMC)
simulation.3)
The simulation requires the two indispensable inputs; the structure factor S(k), given as a function ofwavenumber k, and the liquid density in question. Here, S(k) at 0. 77 GPa and 1040 °C (open circles in Fig. 1)
was taken from Ref. 1, whereas 1.75g/cc resulted from the method given in Ref. 4. The other nontrivial input
is an initial configuration. An aggregation of randomly oriented 2744 tetrahedrons was prepared using themolecular dynamics method developed for a system of SnI4 molecules.5)

Fig. 1. The structure factors of LDL phosphorus used as
input (circles) and resulted from the simulation (red line).

Fig. 2. The resulting radial distribution function plottedagainst radial distance.

Red lines in Figs. 1 and 2 are the resultant structure factor andradial distribution function. The former justifies the simulation result.
As shown in Fig. 3, we visually confirmed that phosphorus atoms in
LDL constitute regular tetrahedrons. The regularity was ensured by
the sharpness of the first peak at 2.2(2) Å, showing theintramolecular P—P correlation.
References
1) Y. Katayama et al., Nature 403, 170 (2000).
2) L. Henry et al., Nature 584, 382 (2020).
3) O. Gereben and L. Pusztai, J. Comput. Chem. 33 2285 (2012).
4) T. Sakagami et al., J. Phys.: Condens. Matter 28, 395101 (2016).
5) S. Sugiyama et al., J. Chem. Phys. 112, 10379 (2000).
Fig. 3. A three-dimensional view for the resultant
aggregate of P4 molecules shown in green.

P6
Local Structure of Ga85.8In14.2 eutectic liquid alloy and its pressure temperature
melting line.
Yimin MIJITI1, Aangela Trapananti1, Lucie Nataf2, Francois Baudelet2, Toru Shinmei3, Tetsuo
Irifune3, Jian Zhong Jiang4, Andrea Di Cicco1,*
1School of Science and Technology, University of Camerino, Via Madonna delle Carceri 9, Camerino, MC
62032, Italy
2
Synchrotron Soleil, L’Orme des Merisiers BP 48, Gif-sur-Yvette 91192, Cedex, France
3
Geodynamics Research Center Ehime University Matsuyama 790-8577, Japan
4
International Center for New-Structured Materials (ICNSM), Laboratory of New-Structured Materials, StateKey Laboratory of Silicon Materials, and School of Materials Science and Engineering, Zhejiang University,
Hangzhou 310027, P. R. China*andrea.dicicco@unicam.it
Keywords : EXAFS, XRD, Local structure, melting line, eutectic GaIn liquid alloy
The structure of the Ga85.8In14.2 eutectic liquid alloy is investigated both under ambient conditions and at highpressure/high temperature using X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) techniques.
The local structure of the liquid alloy at ambient conditions is analyzed using double-edge refinements of the
XAS data. Solid–liquid phase transitions under high-pressure and high-temperature conditions are monitored by
combined XAS and XRD measurements along several quasi-isobaric heating runs, allowing to draw a melting
line up to 10 GPa. The established melting line is found to be slightly below the one of pure gallium (Ga) and tofollow its trend as expected from the eutectic nature of the compound. A series of Ga K-edge X-ray absorption
fine structure (XAFS) spectra measured at different pressures indicates the absence of large structuralmodifications at local Ga sites in the liquid within the investigated pressure and temperature range.

Figure:Best fit double-edge EXAFS refinement of the local structure of GaIn eutectic liquid alloy at ambient conditions.

P7
Development of an Analysis Method for Liquid Electrolyte
at a Lithium Electrode Interface using X-ray Total Reflection*

Koji Kimura1, Kairi Fujii1, Hisao Kiuchi2,†, Kazuki Yoshii3, Tatsumi Hirano2,
Yasuhiro Takabayashi1, Hikari Sakaebe3, and Kouichi Hayashi1
1

Nagoya Institute of Technology, Gokiso, Nagoya, Aichi 466-8555, Japan 2Office of Society-Academia
Collaboration for Innovation, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan 3Research Institute ofElectrochemical Energy (RIECEN), National Institute of Advanced Industrial Science and Technology (AIST)
Ikeda, Osaka 563-8577, Japan*kimura.koji@nitech.ac.jp†
Present address: Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
Keywords: X-ray Total Reflection, Electrolyte, Battery, Synchrotron Radiation
Lithium metal batteries (LMBs) are regarded as promising candidates for post-lithium-ion batteries, becauseof their large theoretical capacity of 3860 mAhg-1 1). LMBs are widely used as primary batteries but not as
secondary batteries, because it is difficult to control the interfacial behavior between liquid electrolytes and thelithium-metal electrode during charging and discharging. So far, extensive studies have been performed tocharacterize the interfacial properties using various techniques such as the optical microscopy2), electron
microscopy3,4), and X-ray photoelectron spectroscopy4). However, these studies have focused on theelectrode-side of the interface, but not on the electrolyte-side. It is important to investigate the electrolyte-side of
the interface in order to comprehensively understand the electrolyte/lithium interface.
In this study5), we used an X-ray total reflection to investigate the electrolyte-side of the interface. Since thedensity of lithium (~ 0.5 g cm-3) is lower than that of typical electrolytes (> 1.0 g cm-3), grazing incidence X-rays
going through the electrolyte can be totally reflected by the electrolyte. Therefore, reflected X-rays from theelectrolyte/lithium interface strongly reflect the electrolyte properties at the interface.
Reflected X-ray from the electrolyte/lithium interface was measured at BL28XU in SPring-8 using a
specially designed cell, where a lithium deposition film on a SiC substrate was inserted. A mixture of propylene
carbonate, 1 mol L-1 of LiPF6, and 50 ppm of H2O was used as the electrolyte. The incident X-ray energy was 28
keV. Two dimensional CdTe detector was used for the measurements.
Figure 1 shows the two-dimensional image of the X-ray intensities measured at the incident angle of 0.035°.
We can clearly observe a total reflection X-ray together with the direct beam, which demonstrates the occurrenceof X-ray total reflection from the electrolyte-side of the electrolyte/lithium interface. Figure 2 shows the X-ray
reflectivity curve. An abrupt drop of the reflected X-ray intensity is observed at 0.042° corresponding to thecritical angle. This value is in good agreement with the calculated value of 0.039°, which further confirms the
successful detection of the total reflection X-ray. In the presentation, details of the cell design and the application
to the in-operando measurements will also be described.
This work was based on results obtained from projects, JPNP16001 and JPNP21006, commissioned by the
New Energy and Industrial Technology Development Organization (NEDO).

Fig. 1 Two-dimensional X-ray intensityfrom the electrolyte/lithium interface
measured at the incident angle of 0.035°.

Fig. 2
X-ray reflectivity
electrolyte/lithium interface.

References
1) X.-B. Cheng et al., Chem. Rev. 117, 10403 (2017).
2) H. Sano et al., Chem. Lett. 42, 77 (2013).
3) Y. Xu et al., ACS Nano 14, 8766 (2020).
4) T. Tsuda et al., Electrochim. Acta 279, 136 (2018).
5) K. Kimura et al., Chem. Lett. 50, 1526 (2021).

curve

of

the

P8
Structure of amorphous Mg85Zn6Y9 alloy as a seed of a long-period stacking
ordered structure*

Shinya Hosokawa1, Jens Rüdiger Stellhorn,2 Akihide Koura,3 Fuyuki Shimojo,3Makoto Tokuda,4 Akira Yoshiasa,4 Nils Blanc,5 Nathalie Boudet,5 Hiroshi Okuda,6Michiaki Yamasaki,7,8 Yoshihito Kawamura7,8
1

Institute of Industrial Nanomaterials, Kumamoto University, Kumamoto 860-8555, Japan, 2 2 Department ofApplied Chemistry, Hiroshima University, Higashi-Hiroshima 739-8527, Japan, 3 Department of Physics,
Kumamoto University, Kumamoto 860-8555, Japan, 4 Department of Earth and Environmental Sciences,
Kumamoto University, Kumamoto 860-8555, Japan, 5 Institut Néel, Centre National de la Recherche Scientifique(CNRS)/University of Grenoble Alpes, 38042 Grenoble Cedex 9, France, 6 Department of Materials Science andEngineering, Kyoto University, Kyoto 606-8501, Japan, 7 Department of Materials Science, Kumamoto University,
Kumamoto 860-8555, Japan, 8 Magnesium Research Center, Kumamoto University, Kumamoto 860-8555, Japan*shhosokawa@kumamoto-u.ac.jp
Keywords: Mg alloys, Partial structure, Anomalous X-ray scattering, XAFS, Reverse Monte Carlo modeling
For recent twenty years, Mg alloys containing Zn and rare-earth impurities discovered by Kawamura et al. [1],which is the so-called KUMADAI Magnesium (denoting the Kumamoto University Magnesium), have achievedmuch attention owing to their potential for applications as new structural materials. As well known, pure Mg isflammable and chemically active as well as the strength and ductility are very poor. By adding small amounts ofZn and Y impurities, however, Mg becomes non-flammable and shows high thermal stability [2]. Moreover, thesealloys exhibit superior mechanical properties, such as a tensile yield strength of about 600 MPa and an elongationof about 8% at room temperature [1,2]. Due to such excellent properties together with an ease of recycling, theseMg alloys are promising as next-generation structural materials, such as for bodies of subways or even aircrafts.
These properties are found to be based on the formation of a long-period stacking ordered (LPSO) phase witha L12 type (fragments of fcc structure) Zn6Y8 clusters, which was observed by a high-angle annular dark-fieldscanning transmission electron microscopy observations [3]. Okuda et al. [4] investigated the phase transition
process of amorphous-to-crystal states in the Mg85Zn6Y8 alloy by using small angle x-ray scattering, and observeda hierarchical transition process; the clustering of the impurity atoms occurs first, and the spatial rearrangement of
the clusters induces secondary, leading to two-dimensional order of the L12 clusters. To obtain proof of theexistence of the clusters in the amorphous phase, Hosokawa et al. carried out Y 3d core-level photo emission
experiments, and the obtained spectrum shows three doublets and one on them coincide well in binding energy
with that of polycrystalline Mg85Zn6Y8 alloy having mostly 100% of the LPSO phase [5]. Therefore, somefragments of the clusters are expected to exist even in the amorphous phase.
In this study, we carried out anomalous x-ray scattering (AXS) measurements at BM02 of the ESRF and x-ray
absorption fine structure (XAFS) experiments at BL9C of the PF-KEK close to the Zn and Y K edges to acquire
direct structural information. The obtained experimental data were analyzed by using reverse Monte Carlo (RMC)
modeling to obtain partial structure factors, Sij(Q), partial pair distribution functions, gij(r), and the corresponding
three-dimensional atomic configurations. An ab initio molecular dynamics calculation was, furthermore,
performed to compare the simulated structures with the experiments.
A large number of the Zn-Zn and Y-Y correlations were found in the first-neighboring shell region unlike thecrystal configurations of the L12 clusters; however, the Zn-Y heteropolar bondings are preferable rather than the
Zn-Zn and Y-Y homopolar bondings in the amorphous phase, which can be considered as the seeds of thecrystalline L12 clusters. A charge transfer from Y to other elements is expected from the estimated atomic radiusof Y. However, a large fraction of the L12 cluster fragments are not observed in contrast to the previous conclusion
without the XAFS data in the RMC analysis [6].
References:
1) Y. Kawamura, K. Hayashi, A. Inoue, and T. Masumoto, Mater. Trans. 42, 1172 (2001).
2) Y. Kawamura, T. Kasahara, S. Izumi, and M. Yamasaki, Scr. Mater. 55, 453 (2006).
3) E. Abe, A. Ono, T. Itoi, M. Yamasaki, and Y. Kawamura, Philos. Mag. Lett. 91, 690 (2011).
4) H. Okuda, M. Yamasaki, Y. Kawamura, M. Tabuchi, and H. Kimizuka, Sci. Rep. 5, 14186 (2015).
5) S. Hosokawa, J. R. Stellhorn, B. Paulus, K. Maruyama, K. Kobayashi, H. Okuda, M. Yamasaki, Y. Kawamura,and H. Sato, J. Alloys Compd. 764, 431 (2018)6) S. Hosokawa, J. R. Stellhorn, B. D. Klee, W.-C. Pilgrim, H. Okuda, M. Yamasaki, Y. Kawamura, N. Blanc,
and N. Boudet, Appl. Phys. Express 11, 071402 (2018).

P9

Collective dynamics of liquid sulfur across the polymerization transition
temperature probed by inelastic x-ray scattering*Shinya Hosokawa1, Yoshinori Katayama2, Satoshi Tsutsui3, Alfred Q. R. Baron4,3
1 Institute of Industrial Nanomaterials, Kumamoto University, Kumamoto 860-8555, Japan, 2 Kansai Photon

Science Institute, National Institutes for Quantum Science and Technology, Sayo 679-5148, Japan, 3 Japan
Synchrotron Radiation Research Institute (JASRI), Sayo 679-5198, Japan, 4 Materials Dynamics Laboratory,
RIKEN SPring-8 Center, Sayo 679-5148, Japan*shhosokawa@kumamoto-u.ac.jp
Keywords: Molecular liquid, Phonon dispersion, Diffusion, Inelastic X-ray scattering.
The so-called l transition in liquid sulfur occurs at about 159°C, which is attributed to the formation of long chain
molecules by breaks and polymerizations of eight-membered sulfur rings at low temperatures. Inelastic x-ray
scattering (IXS) experiments on liquid sulfur were carried out at BL35XU of the SPring-8 [1], below and above
the polymerization temperature (140 and 180°C, respectively) to investigate collective dynamics of this uniquemolecular liquid showing a liquid-liquid phase transition. The obtained IXS spectra were analyzed by using adamped harmonic oscillator (DHO) model [2] with a Lorentzian quasielastic peak.
Figure 1 shows the dispersion relations of the longitudinal acoustic (LA) excitation modes at 140°C (empty
circles) and 180°C (solid triangles) obtained from the DHO model. The solid and dashed lines indicate thedispersions of the hydrodynamic limits obtained from ultrasonic sound velocity data [3]. Only slight differences
are observed in the excitation energies, wQ, although the macroscopic shear viscosity is very different across the ltransition temperature, Tl. Note that the so-called positive dispersion of dynamic sound velocity are observed byabout 40% for both the phases. The width of the LA modes does not change mostly when crossing Tl.
Figure 2 shows the width (half-width at half maximum, HWHM) of the central quasielastic peaks, G0. As seenin the figure, the G0 values at Q < 6 nm-1 beyond Tl are narrower than those below Tl. This result indicates that the
diffusion of sulfur atoms is distinct at the correlation length of more than the molecule size of S8 rings. A
generalized Langevin formalism with a memory function [4] will be applied to obtain microscopic thermodynamic
parameters. The results will be discussed by comparing a previous IXS experiment [5].
0.8

10140 °C 1322 m/s

(meV)

6

ωQ

4

140 °C

0.4

0.2

2
0

140 °C0.6

180 °CΓ0 (meV)

180 °C 1275 m/s

8

0

5

10

15
Q

20

25

30

35

40

-1

(nm )

Fig. 1. Dispersion relations of the LA excitation modes at 140(empty circles) and 180°C (solid triangles). The solid and dashedlines indicate the dispersions of the hydrodynamic limits obtained
from ultrasonic sound velocity data [2].

0.0

180 °C
0

2

4

6

8

Q

(nm )

-1

10

12

14

Fig. 2. HWHM of the quasielastic peak at 140 (empty circles) and
180°C (solid triangles). The solid curves are the guide for eyes.

References:
1) A. Q. R. Baron et al., J. Phys. Chem. Solids 61, 461 (2000).
2) B. Fåk and B. Dorner, Physica B 234–236, 1107 (1997).
3) V. F. Kozhevnikov, J. M. Viner, and P. C. Tayler, Phys. Rev. B 64, 214109 (2001).
4) J. P. Boon and S. Yip, Molecular hydrodynamics (McGraw-Hill, New York, 1980).
5) G. Monaco et al., Phys. Rev. Lett. 95, 255502 (2005).

P10

Phonon dynamics of liquid Hg probed by inelastic x-ray scattering*Shinya

Hosokawa1, Masanori Inui2, Yukio Kajihara2, Ayano Chiba3, Satoshi Tsutsui4,
Alfred Q. R. Baron5,4
1 Institute of Industrial Nanomaterials, Kumamoto University, Kumamoto 860-8555, Japan, 2 Graduate School of

Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8521, Japan, 3 Department of
Physics, Keio University, Yokohama 223-8522, Japan, 4 Japan Synchrotron Radiation Research Institute (JASRI),
Sayo 679-5198, Japan, 5 Materials Dynamics Laboratory, RIKEN SPring-8 Center, Sayo 679-5148, Japan*shhosokawa@kumamoto-u.ac.jp
Keywords: Liquid metals, Phonon dispersion, Inelastic X-ray scattering

References:
1) S. Hosokawa et al., J. Non-Cryst. Solids 312-314, 163 (2002).
2) T. Scopigno, G. Ruocco, and F. Sette, Rev. Mod. Phys. 77, 881(2005).
3) S. Hosokawa et al., Phys. Rev. Lett. 102, 105502 (2009).
4) A. Q. R. Baron et al., J. Phys. Chem. Solids 61, 461 (2000).
5) S. Hosokawa et al., J. Phys.: Condens. Matter 25, 112101 (2013).
6) S. Hosokawa et al., J. Phys.: Condens. Matter 27, 194104 (2015).
7) K. Tamura, M. Inui, and S. Hosokawa, Rev. Sci. Instrum. 70, 144(1999).

IXS intensity (Arb. units)

In 2002, an inelastic x-ray scattering (IXS) measurement on liquid Hg was carried out at room temperature [1] as
one of the pioneering IXS studies on liquid heavy metals. For this experiment, an in-line IXS spectrometer with aresolution of 2.2 meV was used at APS, and the statistical quality was insufficient. Only the longitudinal acoustic(LA) modes could be obtained. The so-called positive dispersion, i.e., larger excitation energies beyond thehydrodynamic prediction at small Q values, was observed by about 20%, which was similar to those in other liquid
metals [2]. However, the indication of extra excitation modes was hardly detected due to an insufficient data quality.
In 2009, we found an indication of transverse acoustic (TA) phonon modes in liquid Ga in addition to the usual
LA modes [3] by IXS with much higher statistical quality [4]. We also detected the TA signals in liquid Sn [5],Zn [6], and transition metals of Fe and Cu [6]. We analyzed the IXS data using current correlation functions, which
are in good agreement with results of an ab initio molecular dynamics simulation [5]. Thereby, the theoretical LA
and TA data show a mixing effect, i.e., mixtures of two excitation branches of quasi-LA and -TA contributions,and the experimental data are always very similar to the theoretical LA result.
Based on these experimental and theoretical understandings, we recall liquid Hg to examine if such an extra
excitation mode exists in liquid heavy metals. IXS experiments were carried out at BL35XU of the SPring-8 using
a high-resolution IXS spectrometer with an energy of about 1.5 meV and an incident x-ray intensity of more than
one order of magnitude [4]. Liquid Hg sample was contained in a single
crystal sapphire cell with a sample thickness of about 0.02 mm and an
liquid Hg
x-ray window thickness of 0.2 mm [7].
300 K
Figure 1 shows IXS intensities of liquid Hg at the selected Q values,
where extra excitation modes may be clearly observed, i.e., including-1
Q (nm ) =the quasi-first and -second Brillouin zone border. As seen in the figure,shoulders are observed at 8-10 meV depending on Q, which are surely
10.6
the LA excitation modes. Compared with the IXS data on liquid lightmetals [2], the IXS signals have quite different features. Further analyses
are now in progress, and the results will be shown in the presentation.
9.2

7.9

6.6
-20

-10

0

10

20

(meV)

Fig. 1. IXS intensities of liquid Hg at selected Q
values.

P11

Inelastic x-ray scattering experiments for liquid GeCu2Te3*

M. Inui1, S. Hosokawa2, S. Tsutsui3, Y. Nakajima4, K. Matsuda4, and A.Q.R. Baron5,3

1

Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima,
Hiroshima 739-8521, Japan, 2 Institute of Industrial Nanomaterials, Kumamoto University, Kumamoto 860-8555,
Japan, 3 Japan Synchrotron Radiation Research Institute (JASRI), Sayo-cho, Hyogo 679-5198, Japan,
4
Department of Physics, Kumamoto University, Kumamoto 860-8555, Japan, 5 Materials Dynamics Laboratory,
RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan*masinui@hiroshima-u.ac.jp
Keywords: atomic dynamics, inelastic X-ray scattering, liquid GeCu2Te3, longitudinal acoustic excitation
Fast phase-change materials (PCMs) such as ternary Ge2Sb2Te5 have been intensively investigated for the lasttwo decades since the fast phase change phenomena between crystalline and amorphous states were utilized in
nonvolatile memory [1]. PCMs for memory devices show strong optical contrast between the crystalline andamorphous states and its origin has been related to the difference in bonding properties between them. Besides
Ge2Sb2Te5, GeCu2Te3 was found to be another candidate of PCMs [2,3]. In the memory device, an amorphous bit
is formed by rapid quenching a liquid spot made by laser beam irradiation. Hence, to investigate atomic
dynamics in the liquid phase is important to understand fast crystallization in PCMs. So far we have carried out
inelastic x-ray scattering (IXS) measurements for liquid Ge2Sb2Te5 to obtain dynamic structure factor S(Q,E),
where Q and E are momentum and energy transfer, respectively. We found that high energy excitation in S(Q,E)
behaves like optical mode with the excitation energy approaching to approximately 20 meV at Q=0 [4]. In thisstudy, we have carried out IXS measurements for liquid GeCu 2Te3 to investigate Q dependence of excitationenergies.
IXS measurements were conducted using high-resolution inelastic x-ray scattering spectrometer at
BL35XU/SPring-8 in Japan. The IXS spectra at 2 < Q < 33 nm-1 were obtained with the energy resolution of
approximately 1.5 meV. After background subtraction, we could obtain S(Q,E) of liquid GeCu2Te3 at 803 K.
S(Q,E) was deconvoluted with a model function composed of a Lorentzian and damped harmonic oscillator(DHO) functions. Fig.1 shows the excitation energies
obtained by a model function of 3-DHO components asa function of Q before averaging the results at similar
Q values. The excitation energies of DHO functions
disperse with Q and the main component (black
circles) is assigned as the longitudinal acoustic mode,
which disperses with Q similarly to liquid GeTe
denoted by a chain curve [5]. Lower excitation energies(open triangles) below the longitudinal acoustic ones
appear at Q > 3 nm-1 and they do not show strong
dispersion staying at approximately 5 meV at 5 < Q <15 nm-1. Interestingly, the longitudinal acoustic
excitation energy exhibits bifurcation at 10 < Q < 20
nm-1, similarly to liquid Ge2Sb2Te5. However, higher
excitation energy (open squares) does not show the
optical mode-like behavior that was observed in liquid
Ge2Sb2Te5.
References:
1) S. R. Ovshinsky, Phys. Rev. Lett. 21, 1450 (1968).
2) Y. Sutou et al., Acta Mater. 60, 872 (2012).
3) T. Kamada et al., Thin Solid Films 520, 4389 (2012).
4) M. Inui et al., Phys. Rev. B 104, 064202 (2021).
5) M. Inui et al., Phys. Rev. B 97, 174203 (2018)

Fig.1 Excitation energies in liquid GeCu2Te3 at 803 K.

P12

Q-gap behavior of low energy excitations in liquid Sb and liquid Bi
observed by inelastic x-ray scattering measurements*

M. Inui1, Y. Kajihara1, S. Hosokawa2,#1, A. Chiba3, Y. Nakajima2, K. Matsuda2,
J. R. Stellhorn1, T. Hagiya4,#2, D. Ishikawa5, H. Uchiyama5, S. Tsutsui5 and A. Q. R. Baron6,5,1

Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima,
Hiroshima 739-8521, Japan, 2 Department of Physics, Kumamoto University, Kumamoto 860-8555, Japan,
3
Department of Physics, Keio University, Yokohama 223-8522, Japan, 4 Graduate School of Science, Kyoto
University, Kyoto 606-8502, Japan, 5 Japan Synchrotron Radiation Research Institute (JASRI), Sayo-cho, Hyogo
679-5198, Japan, 6 Materials Dynamics Laboratory, RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan*masinui@hiroshima-u.ac.jp
Keywords: atomic dynamics, transverse acoustic excitation, inelastic X-ray scattering, liquid Sb, liquid Bi
The dynamic structure factor S(Q, E), where Q and E are
momentum and energy transfer, respectively, has been obtained
for liquid Sb [1] and liquid Bi [2], using inelastic x-ray scattering(IXS) at SPring-8 in Japan. S(Q, E) was deconvoluted by a model
function composed of a Lorentzian and the damped harmonic
oscillators. We have obtained lower excitation energy besides thelongitudinal acoustic excitation in S(Q, E) of these liquids. The
longitudinal acoustic excitation energy experimentally obtained
was in fairly good agreement with that predicted by ab initio
molecular dynamics (AIMD) simulations [3,4,5]. Fig.1 shows thedispersion relation in liquid Sb at 973 K. The excitation energy ofthe longitudinal acoustic mode in liquid Sb (squares) exhibits
flat-topped Q dependence as predicted by an AIMD simulation (amagenta curve) [5]. When we analyzed the data using a modified
damped harmonic oscillator model function, it was clarified thatthe lower excitation energy (triangles) below the longitudinal
Fig.1 The optimised excitation energies
acoustic excitation shows Q-gap behavior. The triangles at 4 < Qof the inelastic components for liquid Sb.
-1< 10 nmwere fitted with a theoretical equation
Also shown are the longitudinal(Q)2=cT2Q2-1/(4M2), where (Q), cT, and M are the excitation(magenta curve) and transverse (crosses)
energy, transverse acoustic sound speed and Maxwell relaxation
acoustic excitation energies obtained bytime, respectively. The broken curve in Fig.1 denotes the
AIMD. The ultrasonic sound speed-1
optimized one and the results show a Q gap of 4.7 nm . The(black line) is 1910 m s−1.
crosses in Fig.1, the simulated transverse acoustic excitationenergy, lie in a lower energy region compared to the triangles,
and similar fits gave a Q gap of 1.4 nm-1. We speculate that the difference between IXS and AIMD arises fromthat IXS observes the transverse acoustic energy in the longitudinal S(Q,E) whereas the simulation can predict
the excitation energy in the purely transverse S(Q,E). From the viscosity estimated from the Q-gap
experimentally obtained, nevertheless, it is inferred that the lower energy excitation arises from the transverse
acoustic excitation in the liquids.

References:1) M. Inui et al., J. Phys.: Condens. Matter 33 475101 (2021).
2) M. Inui et al., Phys. Rev. B 92, 054206 (2015).
3) J. Souto et al., Phys. Rev. B 81, 134201 (2010).
4) M. Ropo et al., J. Chem. Phys. 145, 184502 (2016).
5) R. O. Jones et al., J. Chem. Phys. 146, 194502 (2017).
#1 Present address: Institute of Industrial Nanomaterials, Kumamoto University, Kumamoto 860-8555, Japan.
#2 Present address: Metal Powder Technology Department, Sanyo Special Steel Co., Ltd., Himeji, Hyogo
672-8677, Japan.

P13

Phonon dispersion curves in the type-I crystalline and molten
clathrate compound Eu8Ga16Ge30
Takumi Hasegawa1, *Masanori Inui1, Takahiro Onimaru1, Yukio Kajihara1,
Shinya Hosokawa2,#1, Yoichi Nakajima2, Kazuhiro Matsuda3,#2, Toshiro Takabatake1,
Satoshi Hiroi4, Hiroshi Uchiyama4 and Satoshi Tsutsui4,5
1

Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, 739-8521,
Japan,
2
Department of Physics, Kumamoto University, Kumamoto 860-8555, Japan,
3
Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan,
4Japan Synchrotron Radiation Research Institute (JASRI), Sayo-cho, Hyogo 679-5198, Japan,
5Institute of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, Hitachi,
Ibaraki 316-8511, Japan.
*
masinui@hiroshima-u.ac.jp
Keywords: Inelastic X-ray scattering, thermoelectric material, clathrate compounds, phonon dispersion, ab initio
molecular dynamics simulation
Intermetallic clathrate has been expected as a candidate for high-performance new thermoelectric materials
since the concept of phonon glass-electron crystal was proposed [1]. Among various clathrate compounds, thetype-VIII modification of Ba8Ga16Sn30 exhibits preferable thermoelectric performance [2,3]. To design a suitablepreparing route for the intended modification, it is important to know the properties in the liquid state. We havestudied static and dynamic structures in molten clathrate compound Ba 8Ga16Sn30 to investigate clusters in theliquid state [4]. The pair distribution function in liquid Ba8Ga16Sn30 suggests shorter and longer interatomic
distances in the first coordination shell corresponding to (Ga, Sn)-(Ga, Sn) and Ba-(Ga, Sn) correlations,
respectively. The dynamic structure factor of liquid Ba8Ga16Sn30 obtained by inelastic x-ray scattering (IXS)
exhibits the longitudinal acoustic excitations with a peak profile, and another excitation at a lower energy. The
lower excitation energy in the liquid state was higher than a vibrational energy arising from a rattling motion of aguest atom in the solid state. The result suggests that the host-guest interaction in a solid Ba8Ga16Sn30 clathrate isstrengthened on melting.
In this study, we have carried out IXS measurements of type-I crystalline and liquid Eu8Ga16Ge30 to compare
phonon dispersions between crystalline and liquid states. IXS measurements with the energy resolution of
approximately 1.5 meV were conducted using ahigh-resolution IXS spectrometer at BL35XU/SPring-8
in Japan. IXS spectra of type-I clathrate Eu8Ga16Ge30
were measured at the ambient conditions using a single
crystal piece. As molten Eu8Ga16Ge30 at 993 K was
found to react with sapphire, the molten sample was
sandwiched with glassy carbon in a sapphire cell. Ab
initio phonon calculations based on the density
functional perturbation theory were carried out for
type-I crystalline Eu8Ga16Ge30. The IXS spectra
estimated from the calculated phonon modes are shownin Fig.1 as a color map, where the symbols in Fig.1
denote the excitation energies obtained from IXS
spectra. The symbols fairly well agree with theFig.1 Phonon dispersion of type I clathrate
simulated curves. The dynamics structure factor incompound Eu8Ga16Ge30. Bright curves denoteliquid Eu8Ga16Ge30 exhibits the inelastic excitations ofsimulated phonon excitations and yellow and white
the longitudinal acoustic mode that disperses faster thansymbols are excitation energies obtained by IXS.
the energy simulated for type I crystalline form.
References :1) G. A. Slack, New materials and performance limits for thermoelectric cooling CRC Handbook of
Thermoelectrics, ed. D. M. Rowe (Boca Raton, FL: CRC Press) p 407 (1995).
2) K. Suekuni et al., Phys. Rev. B 77, 235119 (2008).
3) Y. Saiga et al., J. Alloys Compd. 507, 1 (2010).
4) M. Inui et al., J. Phys.: Condens. Matter 30, 455101 (2018).
#1
Present address: Institute of Industrial Nanomaterials, Kumamoto University, Kumamoto 860-8555, Japan.
#2
Present address: Department of Physics, Kumamoto University, Kumamoto 860-8555, Japan.

P14

Density response function of valence electrons in liquid Li*

Kazuhiro Matsuda1, Toru Hagiya2,#, Koji Kimura3, Masanori Inui4, Yukio Kajihara4, Nozomu
Hiraoka5

1
Department of Physics, Kumamoto University, Kumamoto 860-8555, Japan, 2 Graduate School of Science,
Kyoto University, Kyoto 606-8502, Japan, 3 Department of Physical Science and Engineering, Nagoya Instituteof Technology, Nagoya 466-8555, Japan, 4 Graduate School of Advanced Science and Engineering, Hiroshima
University, Higashi-Hiroshima, Hiroshima 739-8521, Japan, 5 National Synchrotron Radiation Research Center,
Hsinchu 30076, Taiwan*

kaz-matsuda@kumamoto-u.ac.jp
Keywords : Liquid metals, Electronic states, Inelastic X-ray scattering, X-ray Raman scattering
The static density response function of electrons provides a unified view in describing the screening effects inmetals. In the electron gas, the derivative of the density response function exhibits logarithmic divergence, whichis responsible for the Friedel oscillation. Theoretical investigations have been made to calculate it in highaccuracy, including the effects of exchange correlations 1), but it has been difficult to confirm the theoretical
calculations experimentally. Recent inelastic x-ray scattering (IXS) techniques using synchrotron radiation allow
us to determine the density response function 2). In principle, dynamical structure factors can be related by thefluctuation dissipation theorem to the imaginary part of response function, and Kramers-Kronig transform of the
dynamic structure factor leads to the real part of response function. In the present study, IXS experiments were
performed on solid and liquid Li 3). Valence electrons of Li are well described by the electron gas model andsuitable for the investigation of screening in simple metals. The measurements were performed at the beamline
BL12XU at SPring-8. IXS spectra were collected in the momentum transfer of 0.30 - 3.47 Å-1 and in the energy
range of 0 to 350 eV. Density response function was constructed that can be compared with a theoretical model.
References:1) G. Giuliani and G. Vignale, Quantum Theory of the Electron Liquid (Cambridge University Press,
Cambridge) 2005.
2) P. Abbamonte et al, Phys. Rev. Lett. 92, 23740 (2004).
3) Toru Hagiya, Kazuhiro Matsuda, Nozomu Hiraoka, Yukio Kajihara, Koji Kimura, and Masanori Inui, Phys.
Rev. B 102, 054208 (2020).
Present address: Metal Powder Technology Department, Sanyo Special Steel Co., Ltd., Himeji, Hyogo
672-8677, Japan#P15
Relationship Between Liquid

Dynamics and Potential Energy LandscapeFranz Demmel1 Louis Hennet2 Noel Jakse3,*
1

ISIS Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX, UK.
ICMN, CNRS and University of Orleans, 45071 Orléans, France.
3
Université Grenoble-Alpes, CNRS, Grenoble INP, SIMaP, F-38000 Grenoble, France.
2*noel.jakse@grenoble-inp.fr
Keywords: Potential Energy Landscape, Ab initio simulation, Molecular dynamics, Entropy scaling law,
Machine Learning.

Understanding evolution of dynamic properties in stable and undercooled liquids as well as their interplay
with their structural features represents an important and still open issue. Cooling a liquid will decrease thefluidity of a particle and the mobility of the neighboring particles, resulting in an increase of the viscosity until
the system comes to an arrest. This process with a concomitant slowing down of collective particle
rearrangements might already start deep inside the liquid state. By considering the Lennard-Jones potential [1] asa generic model and Aluminium [2] a typical liquid metal, it is shown that such a behavior takes its roots in thecharacteristics of the potential energy landscape which provides an attractive picture for these dramatic changes.
The similarity found in dynamics of these two systems as well as with other monatomic liquid metals suggests a
universal dynamic crossover above the melting point. The possible correlation with the excess entropy scaling
law for diffusion is discussed.
[1] A. Saliou , P. Jarry , and N. Jakse, Phys. Rev E 104, 044128 (2021).
[2] F. Demmel, L. Hennet , and N. Jakse, Sci. Rep. (Nature) 11, 11815 (2021).

P16
Selecting atomic fingerprints for high-dimensional neural network
potentials: adaptive group lasso approach
J. Sandberg1,2,3, E. Devijver4, T. Voigtmann2,3, N. Jakse1*
1

Université Grenoble Alpes, CNRS, Grenoble INP, SIMaP, F-38000 Grenoble, FranceInstitut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln,
Germany3
Department of Physics, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf,
Germany
4
Université Grenoble Alpes, CNRS, Grenoble INP, LIG, F-38000 Grenoble, France*
johannes.sandberg@grenoble-inp.fr
Keywords: Molecular Dynamics, Ab initio simulation, Machine learning, Aluminium, Atomic fingerprints,
Interatomic potentials
2Interatomic potentials based on machine learning have developed into a widespread and powerful method ofmaterial science, opening up for ab initio quality simulations at a computational cost near that of classical forcefields. In commonly used approaches such as Behler-Parinello high-dimensional neural network potentials [1]and SNAP [2], among others, an intermediate set of atomic descriptors is used to represent the atomic
environment in lieu of directly feeding atomic positions into the potential. An important component of any suchapproach is to select an appropriate set of atomic descriptors, with a bad choice potentially rendering the final
potential unusable.
In this work we apply variable selection techniques to the Behler-Parinello high-dimension neural network
potential framework in order to automatically select optimal subsets of atomic descriptors from much larger sets .
This removes the need for the developer of the potential to manually select the set of descriptors based on
physical intuition and guesswork, while allowing for computationally faster, more interpretable, and potentiallymore accurate potentials. We present a complete approach to the selection of atomic descriptors for highdimensional neural network potentials, based on the adaptive group-lasso [3]. Although the approach is general,
our work is largely focused on aluminium, owing to its important real-world applications and the existence ofhigh-quality experimental data against which to evaluate the final potential [4]. This also allow us to build upon
our recent study applying a machine learning potential for aluminium to the exploration of solidification
phenomena [5].
Future work will be focused on applying the method to multi-component systems. Each added species will
increase the number of descriptors needed, with variable selection being a promising approach to partly
counteract this added cost. A further line of research will be to explore the introduction of higher level physicalinformation into the training procedure, with the long term aim of studying the link between low-level propertiesof the potential and high-level macroscopic material properties of aluminium and its alloys.

References:
1) J. Behler and M. Parrinello, Phys. Rev. Lett. 98, 146401 (2007)
2) A.. Thompson et al., J. Comput. Phys. 285, 316 (2015)3) V. C. Dinh and L. S. Ho, NeurIPS, 33, 2420 (2020)4) H. L. Peng et al., Phys. Rev. B 100, 104202 (2019)5) N. Jakse et al., arXiv:2201.01370, (2022), submitted

P17

GeO2 glass structure from neural network potential molecular dynamics–dependence of intermediate-range order on density functional approximation*

Kenta Matsutani1, Shusuke Kasamatsu2, Takeshi Usuki2

1

Graduate School of Science and Engineering, Yamagata University, Yamagata, 990-8560, Japan, 2 Faculty of
Science, Yamagata University, Yamagata, 990-8560, Japan*s203002m@st.yamagata-u.ac.jp
Keywords: Density functional theory, Neural network potential, Glass structure, Intermediate-range order
The compaction mechanism of oxides glasses under high pressure has been a topic of high interest in
geoscience with the ultimate aim of understanding the nature of Earth's interior, and GeO 2 glass has been asubject of study in this regard as an analogue to silicate glasses. Although average local structures are relatively
well understood[1], there has been little progress in understanding the intermediate-range structure, which has
been suggested to play a key role in the compaction mechanism under pressure.
Many classical and first-principles molecular dynamics (FPMD)[2] studies have been performed to tackle thisissue. Classical MD relies on empirical data and gives widely varying results depending on the parameterization.
FPMD, on the other hand, is computationally expensive; it is virtually impossible to explore intermediate-rangeorder due to the small number of atoms it can handle. Another issue is the accuracy of the approximations used
in FPMD; standard approximations such as generalized gradient approximation (GGA) neglect the nonlocal
dispersion interaction, which has been suggested to be important for reproducing the pressure-induced structuraltransition[3]. Although more accurate approximations are available, they are even more computationally intensive
and cannot be used directly for long-time simulation of glassy systems. In this work, we address these issues
using neural network potential molecular dynamics (NNP-MD)[4], where FPMD data is fitted with amachine-learning potential to enable large-scale and long-time molecular dynamics simulations with FPMD
accuracy.
We employ VASP[5] code for generating the training data set using three different approximation: thestandard GGA-PBE, vdW-DF2-B86R[6] which contains nonlocal correlation, and HSE06[7] which corrects thedelocalization error in GGA but is ~100 times more costly. A melt-quench process was simulated using FPMD
using GGA-PBE and vdW-DF2-B86R with a 96-atom model to obtain glass structure from crystal. The glassand crystal structure under isotropic pressure were also simulated. The training dataset was then extracted fromthese simulation trajectories, which finally contains 1850 structures and their total energies. The training data for
HSE06-based NNP was collected by recalculating the structures contained in the training data of the GGA-PBE.
We employed SIMPLE-NN[8] code for construction of neural network potential from the training dataset. The
constructed NNPs were used for melt-quench glass formation and compaction simulations using LAMMPS code
on 3240-atom supercell, which are clearly beyond the reach of FPMD.
Total structure factors obtained from our NNP-MD glass structures are shown in figure 1. The GGA-PBE
result is in decent agreement with experiment, although the peak position at high k side is shifted to low k sideand the peak intensity at k = 1.5 Å-1 is slightly underestimated. The discrepancy in the high k region comes fromusual GGA-PBE trend to overestimate covalent bond lengths. The low k peak at 1.5 Å-1 implies
intermediate-range order in the glass network. The vdW-DF2-B86R showed a larger deviation from experiment,
which was surprising since we expected an improvement due to inclusion of nonlocal interactions. HSE06, themost expensive approximation examined here, yields almost perfect agreement for the bond length and best
agreement in the low-k intensity. Moreover, only HSE06 could reproduce the preservation of the four-fold Ge-O
coordination up to 4 GPa observed in experiment. In summary, NNP technology enabled large scale MD
simulation of glass formation with HSE06 accuracy, which turned out to be imperative for accurate descriptionof the pressure-induced structural transition in thisprototypical glass network.
References
1) P. S. Salmon et al., Phys. Rev. Lett. 96, 235502 (2006).
2) X. F. Zhu et al., Phys. B: Condens. Matter 404 4178
(2009)
3) D. Marrocchelli et al., Mol Phys. 107 443 (2009)4) J. Behler et al., Phys. Rev. Lett., 98 146401 (2007)
5) G. Kresse et al., Phys. Rev. B 52 11169 (1996)
6) I. Hamada, Phys. Rev. B 89 121103(R) (2014)
7) A. V. Krukau et al., J. Chem. Phys., 125 224106 (2006)
8) K. Lee et al., Comput. Phys. Commun. 242 95-103 (2019)

Fig. 1. Each total structure factors were obtained from
NNP-MD and experiment[1].

P18
Optical properties of molten pure copper by density functional theory*

Susumu Kato1, Shota Ono2, Atsushi Sunahara3,Yuji Sato4, Masahiro Tsukamoto4

1

Research Institute for Advanced Electronics and Photonics, National Institute of Advanced Industrial Scienceand Technology (AIST), Tsukuba, 305-8568, Japan, 2 Department of Electrical, Electronic and Computer
Engineering, Gifu University, Gifu, 501-1193, Japan, 3 Center for Materials Under eXtreme Environment(CMUXE), School of Nuclear Engineering, Purdue University, West Lafayette, 47907, USA, 4 Joining and
Welding Research Institute (JWRI), Osaka University, Ibaraki, 567-0047, Japan*s.kato@aist.go.jp
Keywords: Liquid metal, Density-functional theory, Joint density-of-state, Dielectric function,

Density of States (states/eV)

Copper is widely used in automobile batteries, motors, and so on due to high electric conductivity. The
welding of copper, which is a highly infrared-light-reflective material, is performed with blue and green lasers in
addition to an infrared laser1-3). Quality of the laser welding is determined by the absorptivity, which strongly
depends on the laser wavelength and temperature.
Optical properties of pure copper have been a subject of many studies since the 1950's4-9). Some pioneeringstudies of electronic structure in liquid have been carried out using ab initio simulations10-11). Optical propertiesof high-temperature solid and liquid copper in the visible light were not so clear in comparison with them in theinfrared light12-14).
In this paper, the optical properties of molten pure copper
9
investigated by the Density Functional Theory (DFT) using(a)8
QUANTUM ESPRESSO package15). We used the7
pseudopotentials Cu.pbe-dn-rrkjus_psl.1.0.0.UPF from the6
QUANTUM ESPRESSO pseudopotential data base. The
5electron density of states (DOS) in face-centered cubic and4liquid copper are shown in Figures 1(a) and (b). The density
3of 7.99 g/cc is chosen at the melting temperature of copper.
2
The simulations were performed on a supercell containing 32
1
atoms and its size was (7.5Å)3.
0
The change of the absorptivity at the phase transition is
-5
-4
-3
2
-1
0
1
considered using the joint density of states and complex
Energy (eV)dielectric constant obtained from DTF.
9

Density of States (states/eV)(b)References (Example: non-mandatory, 10 point):
81) Y. Sato et al., Appl. Surf. Sci. 480, pp. 861–867 (2019).
72) S. Grabmann et al., Procedia CIRP 94, pp. 582-586 (2020).
63) M. Hummel et al., J Adv Join Process 1, 100012 (2020).
54) L.G. Schulz, J. Opt. Soc. Am. 44, pp.357–362 (1954). L.G.
4
Schulz and F.R. Tangherlini, J. Opt. Soc. Am. 44, pp.
3
362–368 (1954).
25) S. Roberts, Phys. Rev. 118, pp.1509–1518 (1960).
16) G.P. Pells and M. Shiga, J. Phys, C 2, 1835–1846 (1969).
07) P.B. Johnson and R.W. Christy, Phys. Rev. B 6,
-5
-4
-3
2
-1
0
1
pp.4370–4379 (1972). P.B. Johnson and R.W. Christy, Phys
Energy (eV)
Rev B 11, pp.1315–1323 (1975).
Fig. 1. Electron density of states (DOS) in (a) face-centered
9) D.J. Nash and J.R. Sambles, J. Mod. Opt. 42, cubic and (b) liquid copper.
pp.1639–1647 (1995).
10) E.G. Maksimov et al., J. Phys. F: Met. Phys. 18, pp.833-849 (1988)
11) A. Pasquarello et al., Phys. Rev. Lett. 69, pp.1982–1985 (1992).
12) J.C. Miller, Phil. Mag. 20, pp.1115–1132 (1969).
13) N. R. Comins, Phil. Mag. 25, pp.817–831 (1972).
14) K. Ujihara, J. Appl. Phys. 43, pp.2376–2383 (1972).
15) P. Giannozzi et al., J. Phys. Condens. Matter 21, 395502 (19pp) (2009). P. Giannozzi et al., J. Phys.:
Condens. Matter 29, 465901 (2017). Giannozzi, P. et al., J. Chem. Phys. 152, 154105 (2020).
.

RP1

Development and optimization of sulfur-containing novel Ti-based Bulk
Metallic Glasses and the correlation between primary crystalline phases, thermal
stability and mechanical properties*

Lucas Matthias Ruschel1, Bastian Adam1, Oliver Gross2, Nico Neuber1, Maximilian Frey1,
Ralf Busch1
1

Chair of Metallic Materials, Saarland University, 66123 Saarbrücken, Germany
Amorphous Metal Solutions GmbH, 66424 Homburg, Germany*
lucas.ruschel@uni-saarland.de
Keywords: Bulk metallic glass, Titanium alloys, Mechanical properties, Thermal stability, Sulfur, Phasetransformation
2

Amorphous metals possess a disordered atomic structure which is responsible for their high strength andelasticity in comparison to their crystalline counterparts. Recently, our group reported on the bulk glass
formation in the Ti-Ni-S and Ti-Ni-Cu-S system [1], [2]. As sulfur addition is very effective in both systems, its
influence on the Ti33.4Zr33.3Cu33.3 eutectic composition in terms of glass forming ability, thermal stability andmechanical properties was investigated by conventional X-ray diffraction, differential scanning calorimetry andthree-point beam bending experiments. A novel bulk glass forming region with a critical casting diameter of
4 mm was found in the quaternary Ti-Zr-Cu-S system, however, brittle fracture behavior was predominant.
Various alloying strategies were employed to improve mechanical properties and a compositional transition frombrittle to ductile has been found (e.g. for Ti36Zr33.5Cu24.5S6). A change of the primary precipitating phases from a
C14 Laves (Frank-Kasper structure) to an intermetallic (Ti, Zr)2Cu phase (and vice versa) can be observed, as
well as a stabilization/destabilization of the glass transition. The origin of a thermally unstable behavior resides
in the easy formation of the icosahedral phase upon heating, which is structurally close to the supposedly
predominant icosahedral short-range order in the amorphous state. The systematic study carried out in this work
indicates a strong correlation between primary crystallizing phase and thermal stability with the mechanicalproperties in Ti-based bulk glass forming alloys. The transition from the Laves to the intermetallic phase resulted
in a distinct glass transition and ultimately improved mechanical properties with ductility in bending. It is
assumed that this enhancement is directly related to the destabilization of the icosahedral short-range order in theamorphous structure.

Figure 1 (a) XRD patterns of 5 mm partially crystalline samples. The primary precipitating phase is changing
from a C14 Laves phase to the intermetallic (Ti, Zr) 2Cu phase. (b) In addition, the thermal stability of fully
amorphous samples increases as the icosahedral phase (first exothermic event) is pushed to higher temperatures.
(c) The change in primary phase and stabilization of the glass transition indicate a destabilized icosahedral
short-range order, ultimately lead to a ductile fracture behavior in 3-point beam bending.

References:
1) Gross, O. et al, Journal of Physics: Condensed Matter, 84(20), 4029–4031 (2020)
2) A. Kuball et al., J. Alloys Compd., vol. 790, pp. 337–346, Jun. (2019)

RP2
Structural analysis of etidronate disodium*

H. Shimakura1, T. Hashizuka2, and K. Ohara3

1

NUPALS, Niigata-shi, 956-8603, Japan , 2 Dainippon Sumitomo Pharma Co., Ltd., Osaka, 554-0022, Japan,
Japan Synchrotron Radiation Research Institute (JASRI), Sayo, Hyogo 679-5198, Japan
Keywords: RMC, MD simulation, Medical supplies

3

S (Q)

S (Q) +10
10

Cryobiology

B. L. Barnett, L. C. Strickland, Acta
[2]
Crystallographica, Section 35 (1979) 1212

andTetrahydrate crystals

S (Q)+5
Anhydride crystals

00Tetrahydrate crystals（calculation)

2

4
6
-1
Q (Å )

8

10

Fig.1 Structure factors of etidronate II sodium
tetrahydrate crystals and anhydride crystals
obtained experimentally and calculated from thestructure reported by Barnet et al.

3
2
1
0

-1
-2
-3
0

References:
E.
Yonemochi,[1]
Cryotechnology, 51 (2005) 25

20

G (r)

Generally,forlow-molecular-weight
pharmaceuticals, the active pharmaceutical ingredient(API) has been formulated as a solid (crystal) formulationfrom the viewpoint of drug stability and homogeneity. On
the other hand, amorphous formulations of the API are
increasingly being developed for difficult-to-watersoluble drugs, transdermal drugs, liposome formulations,and other products. However, amorphous formulations
need to be investigated in detail due to the high risks
associated with crystal transition and stability.
This study is a structural study of the amorphous
molecular structure of disodium etidronate (Didronel),
which is currently marketed as an active pharmaceuticalingredient in an amorphous state. It has been foundthat thestability and molecular shape of the amorphous statevaries depending on the generation method. With theincrease in the number of pharmaceuticals in the form,
methods for evaluating the stability of these amorphous
drug products have been developed not only by
conventional thermal analysis and long-term stability
testing, but also by predicting physical stability based onmolecular mobility [1], and there is a need to establish amethod that can be used for many amorphous drug
products.
Figure 1 shows the structure factors S (Q) of disodium
etidronate tetrahydrate and anhydride crystals and thestructure factor calculated based on the tetrahydrate crystal
structure reported by Barnet et al. The tetrahydrate crystals
measured in this study show almost the same spectra as the
structure reported by them.
Figure 2 shows the reduced pair distribution function
G (r) for the disodium etidronate tetrahydrate andanhydride crystals, showing that there is slight change inthe peaks associated with molecular geometry at distances
below 4.0 Å, indicating that the structure of the etidronate
molecule remains unchanged. On the other hand, in theregion corresponding to the intermolecular distance above
4.0 Å, differences between the tetrahydrate and anhydride
crystals are apparent. In particular, the anhydride crystal
shows a peak at 4.0-5.0 Å, indicating that there is adifference in the arrangement of etidronic acid molecules.
In my poster, we will mention to structural comparisonsof them in crystals and amorphous.

2

Tetrahydrate crystals
Anhydride crystals
4
6
8
10
r (Å)

Fig.2 Reduced pair distribution function ofetidronate II sodium tetrahydrate crystals andanhydride crystals

RP3
Topological analysis for α-AgI*

S. Tahara1, H. Shimakura2, and T. Fukami1

1

Univ. of the Ryukyus, Nishihara-cho, 903-0213, Japan, 2 NUPALS, Niigata-shi, 956-8603, Japan
Keywords: Superionic conuctor, MD simulation, persistent homology analysis, Structure.
AgI is well known as a superionic conductor in the high temperature solid (α) phase where Ag ions can migrate
through interstitial sites of b.c.c sublattice of I ions.1) In the case of typical salts such as RbCl, the first neighboring
distance of cation-cation correlation is the almost same as that of anion-anion in both solid and liquid phases,
however the first neighboring distance of Ag-Ag in AgI is anomalously close.2) The anomalous Ag-Ag correlationin α- and molten AgI has been studied by several methods,
for example reverse Monte Carlo method3-4), classical MD
simulations,5) and ab initio MD simulations6). The
mechanism of Ag conduction is discussed from theviewpoint of the one-dimensional stream of Ag ions3-4) andthe cooperation between Ag and I ions6). The observationof the first sharp diffraction peak at Q = 1 Å-1 in the total
structure factor for AgI and the partial structural factor of
Ag-Ag are interpreted to be due to such an anomalous
distribution of Ag ions. In order to reproduce such an
anomalous Ag distribution by classical MD simulation,
the polarizable ion model (PIM) which incorporates thepolarization effect of anions by a self-consistent algorithm
is important5).
In the present study, we carried out the classical MD
simulation for α-AgI at 573 K with PIM and analyzed theatomic configurations by means of persistent homology
analysis method which is new geometical mathmatics
method. Figure 1 shows that the 1-dimensional persistence
diagram (PD) for Ag distribution for rigid ion model(RIM) and PIM simulations. Obviously, the PD
distribution spreads due to the anion polarization,
indicating that the two-dimensional polygons found in the
distribution of Ag ions are diversified. In the presentation,
we will report on the details of PD analysis, including 2Fig.1 1-dimensional PD for Ag distribution in αdimensional PD.
AgI at 573 K of RIM and PIM simulations.

References:
1) C. Tubandt and E. Lorentz, Z. Phys. Chem. 87, 513 (1914).
2) Y. Tsuchiya, J. Phys. C: Solid State Phys. 20, 5001 (1987).
3) Y. Kawakita, S. Tahara, H. Fujii, S. Kohara, and S. Takeda, J. Phys.:Condens. Matter 19, 335201 (2007).
4) S. Tahara, H. Ueno, K. Ohara, Y. Kawakita, S. Kohara, S. Ohno and S. Takeda, J. Phys.: Condens. Matter 23,
235102 (2011).
5) V. Bitrián and J. Trullás, J. Phys. Chem. B 112, 1718 (2008).
6) F. Shimojo, T. Inoue, M. Aniya, T. Sugahara, and Y. Miyata, J. Phys. Soc. Japan 75, 114602 (2006).

RP4

Glass transition temperature of nickel based binary alloys and its
interparticle dynamics features*

Dmitrii Fleita*,1,2

1

HSE University, Moscow, 101000, Russia
Joint Institute for High Temperatures of the Russian Academy of Sciences, Moscow, 125412, Russia*
fleyta.du@phystech.edu
Keywords: molecular dynamics, metastable states, spatio-temporal correlations, vitrification.
2

Particle transport processes in dense melts are governed by highly cooperative phenomena. This makes
available to predict their physical properties based on their structural-temporal properties.
We discuss the dependence of self- and inter-diffusion and collective coefficients on temperature andcomposition of melts. Earlier it was shown that certain spatio-temporal characteristics reflect the processes oftransfer and glass transition [1]. The analysis of the behavior of the glass transition temperature is compared withexperimental data for similar systems [2,3]. The analysis of interparticle interactions demonstrates a similar
dependence of partial functions on the percentage composition of alloys found earlier in experiment [4] and MD
simulation [5], reaching saturation with a change in the qualitative nature of the collective transfer of melt
particles.
This work was supported by the grant of the President of Russian Federation (project No. 17-79-20391). The
authors acknowledge the JIHT RAS HPC and HSE University HPC Cluster ”cHARISMa”.
References:
1) D. Fleita, G. Norman and V. Pisarev, J. Phys.: Condens. Matter 32, p. 214009 (2020)2) P. Kuhn, J. Horbach, F. Kargl, A. Meyer and T. Voigtmann, Phys. Rev. B 90, p. 024309 (2014)3) B. Nowak, D. Holland-Moritz, F. Yang, Th. Voigtmann, Z. Evenson, T.C. Hansen
and A. Meyer, Phys. Rev. B 96, p. 054201 (2017)4) B. Nowak, D. Holland-Moritz, F. Yang, Th. Voigtmann, T. Kordel, T.C. Hansen
and A. Meyer, Phys. Rev. Mat. 1, p. 025603 (2017)5) D. Fleita, G. Norman and V. Pisarev, J. Phys.: Conf. Ser. 1147, p. 012015 (2017)

RP5
Local density fluctuation realized in Nb-Ni amorphous alloys*

T. Kawamata1, N. Takehara1, R. Kuroda1, K. Sugiyama1

1

Institute of Material Research, Tohoku University, 980-8577, Japan
kawamata@tohoku.ac.jp
Keywords: Amorphous alloy, Anomalous X-ray scattering, Reverse Monte-Carlo simulation.

The details of short and medium-range ordered structures realized in amorphous alloys are associated with theirinteresting material properties such as high GFA and high strength. For the understanding the fine structure ofamorphous alloys, AXS-RMC, which is a combination of anomalous X-ray scattering (AXS) and RMC-simulation,
could be counted as one of the powerful analytical tools1). In this study, we report on the unique geometricalfeatures with respect to the nearest neighbor pairs and the diversification of short-range ordered structures observedin Nb-Ni amorphous alloys2).
Nb-Ni amorphous alloys were prepared by a copper single roll rapid quenching method. The anomalous X-ray
scattering measurements were performed at the beam line BL-7C, high energy accelerator research organization(Tsukuba, Japan). In the present AXS analysis, X-ray diffraction measurement using two different energies werecarried out at the Nb and Ni K edges. RMC analysis was performed using the environmental structure information
obtained by the AXS as a constraint, and a three-dimensional amorphous structure model (RMC-model) was
created so as to reproduce the environmental structure information around the constituent elements. The DRP(Dense Random packing of hard sphere) -model was used as the initial model for the RMC simulation.
As an example, the result of RMC simulation for Nb60Ni40
amorphous alloy is shown in Fig. 1. The DRP-model reproduces thefundamental features of the ordinary (Qi(Q)) and environmental
interference functions (ΔQiNb(Q) and ΔQiNi(Q)) obtained from theexperiments, however the fine osculation profiles such as the split
observed at the second peak at about 50 nm-1 for every Qi(Q)s could
not be reproduced well. On the other hand, the RMC-model is able
to reproduce the details of both the ordinary and environmental
interference functions. This fact indicates that RMC-model createdby AXS-RMC method allows to discuss the structural role ofconstituent elements in Nb-Ni amorphous alloy. Fig. 2 shows the
Nb-Nb partial distribution functions, g(r)s calculated from DRP and
RMC-models of Nb-Ni amorphous alloys. The g(r)s calculated from
Fig. 1 Ordinary and environmental
DRP-model show similar shape in the nearest neighbor region forinterference functions of Nb40Ni60
amorphous alloy calculated from DRP
all alloy compositions, indicating single peaks near the sum ofand RMC-model.
Goldschmidt radius for Nb (0.294nm). On the other hand, thepresent AXS-RMC analysis suggests the characteristic Nb-Nb
correlations with a harmony of short (0.250 nm) and long (0.320nm) distances. The subsequent CNA (common neighbor analysis)
with respect to the Nb-Nb correlations revealed the unique CN
structures of [666]CN and [433]CN. The former [666]CN structure isassociated well with dense tetrahedral packing and developed in the
Nb-Nb correlations on the short-range region (0.240 nm to 0.280nm). The latter [433]CN structure represents the correlations
developing on the long-range side (0.310 nm to 0.340 nm), which is
associated with low-density octahedral filling. In other words, thevariation of Nb-Nb pairs observed at the nearest neighbor region is
attributed to the fluctuation of local density in Nb-Ni amorphousalloys, which could not be explained by DRP-model.
1) T. Kawamata, T. Muto and K. Sugiyama, Mater. Trans. 62, 20(2021).
2) L. Xia, W. H. Li, S. S. Fang, B.C. Wei and Y. D. Dong, J.
Appl. Phys. 99, 026103 (2006).

Fig. 2 Nb-Nb partial distribution functions,g(r)s of DRP and RMC-models for Nb-Ni
amorphous alloys. Vertical dotted lines inthis figure indicate sum of Goldschmidt
radius for Nb atoms.

RP6
Unsupervised topological learning of crystal nucleation in pure metals
Sébastien Becker1,2, Emilie Devijver2, Rémi Molinier3, *Noel Jakse1
1

Université Grenoble-Alpes, CNRS, Grenoble INP, SIMaP, F-38000 Grenoble, France.
Université Grenoble-Alpes, CNRS, Grenoble INP, LIG, F-38000 Grenoble, France.
3
Université Grenoble-Alpes, CNRS, IF, F-38000 Grenoble, France.
*noel.jakse@grenoble-inp.fr
Keywords: Atomic structures, Molecular dynamics, Homogeneous nucleation, Topological data analysis,
Machine learning.
2

Crystal nucleation in liquids is a fundamental process that we experience daily in nature (e.g., formation ofice) or through the human industry and creation of materials. Such a phenomenon is initiated at atomic scales
that are still experimentally inaccessible, making the understanding of the underlying physics challenging. Thus,
large-scale atomic-level simulations have been shown to provide a powerful way to investigate detailed
information at such small spacetime levels [1]. From this perspective, we propose an unsupervised machinelearning method [2] for the autonomous structural analysis of materials based on original topological descriptorsof local atomic structures computed from persistent homology [3, 4]. From this protocol [5], a model is learnedin course of nucleation in order to identify, without a priori on a system, clusters of atomic structures which arisein the process. This method has been applied to investigate several molecular dynamics configurations up to 10
million atoms undergoing homogeneous nucleation at the nose of the time-temperature-transformation curves offour pure metals chosen for the variety of their crystalline phase [6]; namely: Tantalum (Ta) and Zirconium (Zr)for body-centered cubic, Aluminium (Al) as face-centered cubic and Magnesium (Mg) for hexagonal closepacked. Precursors of the crystalline orders are highlighted as emerging from low fivefold symmetry regions in
structural heterogeneities of the supercooled liquids and a general behavior for all the nuclei and embryos showsa concurrent emergence of the translational and orientational orderings. This unsupervised learning approach
more generally opens the route to further investigation of atomic level structure-dependent phenomena.
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[3] H. Edelsbrunner, D. Letscher, and A. Zomorodian, Discrete Comput Geom 28, 511 (2002).
[4] A. Zomorodian and G. Carlsson, Discrete Comput Geom 33, 249 (2005).
[5] S. Becker, E. Devijver, R. Molinier, and N. Jakse (Phys. Rev. E, accepted 2022).
[6] S. Becker, E. Devijver, R. Molinier, and N. Jakse, Sci. Rep. (Nature) 12, 3195 (2022).