A Grant-in-Aid for Scientific Research on Innovative Areas
The Area Number 2509 (2013-2018)

MOLECULAR ARCHITECTONICS
Orchestration of Single Molecules for Novel Functions
News Letter No.12March 2018

A03 Dr. Akitoshi Shiotari
Structural strain in a hydrocarbon on asurface produces an unprecedented molecule

A04 Dr. Megumi Akai
Signature analysis of single molecules using
their noise signals

Controlling the structural deformation of organic

We explored the ability of single molecules tomolecules can drive unique reactions that cannot

affectbeinduced

onlygeneratedbycarbonornanotube-based nanoscale electronic devices. The

However,

indevices were exposed to different large molecules,

conventional organic synthesis, it is difficult tocausing some to bind to the carbon nanotube

control

procedures.

inpolycyclicsurface. It was found that different molecules gaveWe

recentlyunique noise signals related to the properties of thedemonstrated a characteristic rearrangement of anmolecules. The strength of the interaction between

azulene-derivative PAH on a metal surface driven

the carbon nanotubes and molecules was able to beby the intramolecular structural strain (A. Shiotari,

predicted from the obtained noise signals.

aromaticskeletal

thermal,noise

optical,electrochemical

bythe

rearrangementhydrocarbons(PAHs).

T. Nakae, et al., Nat. Commun. 2017, 8, 16089).
Noncontact atomic force microscopy visualized thecarbon skeletons of reactants, intermediates, andproducts of the on-surface reaction. An azulenegroup in the PAH was converted into a fulvaleno
group, so as to eliminate the structural strain
localized in the azuleno moieties on the surface.
Such strain-induced reactions of PAHs would be auseful approach to designing and fabricating
unprecedented, functional nanocarbon materials.

The noise signal is generated by single molecules
because the adsorbed molecule generated a trap
state in the carbon nanotube, which changed its
conductance. The ability to characterize single
molecules using highly sensitive nanoelectronics is
an exciting prospect in the field of sensors,particularly for neuro- and biosensor applications.
Improved knowledge of the molecular-level origin
of noise should lead to the development ofelectronics that use noise to improve theirperformance rather than degrade it.

~MolecularA01

A02
Synthesis and Applicaitonof disilane-bridged donoracceptor molecules whichhave triarylamine moieties
Mr. Tsukasa Usuki(University of Tokyo)

Synthesis of !-Expanded
Azacoronene Derivatives
toward Post-Nanocarbon

Mr. Kosuke Oki(Ehime University)
Doped large polycyclic aromatic hydrocarbons

Recently, donor-acceptor molecules consisting of(PAHs) with heteroatoms is one of the key

electron-donating (D) and electron-accepting (A)exploration

nanographenemoieties have received attention because of theirresearch. Nonplanar PAHs also have muchpotential for photonic and electronic materials.

attention because of their unique structure andThey

physical properties. However, the figuration ofproperties, however, in the solid state, !-curved -systems with internal heteroatoms has
been still challenging.

conjugated molecules often exhibit weak emission

areas

Recently,
fused-OPN

we2

as

in

current

successfullyasynthesized

nitrogen-doped

curvedshowedremarkable

light-emittingby aggregation-caused quenching (ACQ) due to!–!

stacking.

Previously,

wesynthesized

disilane-bridged DA molecules which displayed

nanocarbon in only two steps from commerciallystrongavailable

octafluoronaphthalene

nucleophilic

substitution

oxidative

decrease !! interactions and suppress ACQ.
In this work, we focused on the application of this

cyclodehydrogenation. The molecular structure oftype molecules to organic light-emitting diodes

2X-ray(OLEDs). Firstly, we applied DA molecules

diffraction. In contrast to the planar structure ofreported previously. However, electrolumine-hexapyrrolohexaazacoronene

1),

scence was not observed because of their large

negatively curved structure owing to formation ofHOMO-LUMO gap and extremely low electric

heptagons was detected. The electrochemicalconductivity. Next, we synthesized new disilane-properties of 1 and 2 were studied by cyclic

bridged DA molecules possessing triarylamine

voltammetry (CV) and exhibited up to three andgroups as donor moieties. Triarylamine groups

four reversible oxidation peaks, respectively. The

are well-known as strong electron-donating andUV-vis-NIR spectra of 2 changed dramaticallyhole-transportingwith isosbestic points when the oxidant was

triarylamine groups, reducing HOMO-LUMO

added incrementally to the solutions. This result

gap

supports the sequential oxidation of the -systems from a neutral to a radical cation,expected. The device was fabricated by vacuum

dication, and then to a radical trication. The

figure.

further investigations for the dynamic behavior ofblue-green electroluminescence. This is the first

2 are under way.

report of electroluminescence from disilane-wasconfirmed

byandvia

single-crystal(HPHACsolidandstateemission.

properties.

improving

DisilaneBycarrierunits

introducing

mobility

weredeposition and the construction is shown inConsequently,

thedevice

exhibitedbridged DA molecules in undoped devices.

Architects~
A03

A04
Design of unique informationprocessing coarse-grained
devices mimicking foraging
behavior of honeybee swarm

Single-molecule spintronics

Mr. Toshihiko Tanabe(Yokohama NationalUniversity)

Mr. Keigo Minode(Osaka University)
I am engaged in research about magnetic fieldWhatdependence of resistance, i.e., magnetoresistanceprocessingway(MR)includingsingle-moleculeof

single-moleculejunctions

withisthemostappropriatefor

informationcoarse-grained

devices

devicesand

ferromagnetic electrodes.

single-electron devices? We think it has not been

MR is an important phenomenon for magnetic

established yet. As one approach to find thesensors and is used in a reading head of hard disk

suitable way, we focus on a natural phenomenon,

drives.

specifically, the behaviors of honeybee swarm.

Single-molecule spintronics is paid attention toRecently, a “nature-inspired” or “biomimetic”

exhibit higher MR ratio due to spin-dependent

technology has been attracting attention forelectronic states caused by electronic couplingdeveloping

betweenapplyingferromagnetic

electrodes

andtheinnovative
emerging

functional

nanoscalesystemsdevices.

Inmolecule.

particular, the foraging behavior of honeybees isInterpretation of experimental MR was difficult

focused on as architecture for an electronic circuit.

because of the huge Anisotropic MR originate

It is known that the honeybees show two foraging

from ferromagnetic nano-junctions.

behaviors, namely, a probability search and aTo detect MR originated from single-molecule“wagglejunctions, I focused on modulation of junction

combining these behaviors, it can be consideredsymmetry because theoretical study predictedthatthat MR ratio will change according to symmetry

information-processing act. For constructing aof junction. I measured Ni/carbazole 3-mer/Ni

new system, we are now designing, simulating,single-molecule junctions. Previous study showed

andthat symmetry of molecular orbital of carbazole

mimicking the behavior. We are here focusing on

3-mer is deformed by applying voltage between

a single-electron circuit as one of coarse-grainedelectrodes. Therefore, voltage dependence of MRdevices

would contain information on characteristics

system for it. The results of the simulation

originatedindicatedtomolecule. I have constructedmeasurement system and obtained results.

dance”

the(sharingforagingevaluatingandbehavior

ourisacoarse-grained

designingthatinformation).

oura

By

uniquecircuithoneybee-inspired
honeybee-inspired

single-electron circuit can perform functional
information

processing.

8th Workshop for Young Researchers
2 - 3 December 2017
TKP Matsuyama Conference Center, Matsuyama, Ehime

On the first day, we received two lectures.

On the second day of the workshop, aThe first lecture was given by invited speakers

group discussion was held in English on theMr.

topic of "The Current Status and Future ofSatoandMr.

Nagayoshi(RenesasElectronics Corporation) on the topic ofMolecular‘Business Trends of Semiconductors andresearchers, including international members,

Expectations for Chemical Engineers’. We

were separated into four groups. For the firstlearnedhour, they summarized the current issues

aboutrecenttrends

inthewas given by invited speakers Dr. Akai (A04)

experimenting,and Dr. Yamada (A03) on the topic of‘Howpossible solutions. Then in the second hour, ato Make your Paper Attractive’. They gave us

representative from each group explained

an interesting talk and useful advice. In thetheir discussion results. Wide points of view,

second lecture workshop, we discussed howfrom single molecule function and device

tostructure,

goodtitle

andsummarize

tofirsthand

young

based

a

their

20

semiconductor industry. The second lecture

writeonArchitectonics".

andsystemexperience

activelyindiscussed

integration,

wereexperimental results for our paper. Thisdeliberated and many inspiring ideas werelecture was helpful in learning how to make aproposed.

paper and write a thesis in English. We giveopportunity for young scientists to practice

our thanks to all the speakers for theiroral English and share thoughts from different

excellent lectures.

fields.

This(A01 Kohta Muramatsu)

Edited by “Molecular Architectonics” Chief Office
1-3 Machikaneyama, Toyonaka, Osaka 560-8531
Mail: office@molarch.jp

workshopwasagreat(A04 Xiang Yin)