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Vol.45 No.6
JournalJournal of the Magnetics Society of Japan
Electronic Journal URL: https://www.jstage.jst.go.jp/browse/msjmag

2021

Thin Films, Fine Particles, Multilayers, Superlattices
Inﬂuence of B Content on the Magnetostrictive Properties of Single-Crystalline, Poly-Crystalline, and発行（公社）日本磁気学会 〠101‒0052 東京都千代田区神田小川町2丁目8番地
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Amorphous Fe-Co-B Alloy Films
Y. Nakamura, M. Ohtake, T. Kawai, M. Futamoto, F. Kirino, and N. Inaba…136

Magnetism and Astronomical Infrared Spectrum of Fullerene C60 and Void Induced Graphene Molecules
N. Ota, A. Li, L. Nemes, and M. Otsuka

…142

45

HP: http://www.magnetics.jp/ e-mail: msj@bj.wakwak.com
Electronic Journal: http://www.jstage.jst.go.jp/browse/msjmag

6

2021

INDEX

Journal of the Magnetics Society of Japan
Vol. 45, No. 6
Electronic Journal URL: https://www.jstage.jst.go.jp/browse/msjmag

CONTENTS
Thin Films, Fine Particles, Multilayers, Superlattices
Influence of B Content on the Magnetostrictive Properties of Single-Crystalline, Poly-Crystalline, andAmorphous Fe-Co-B Alloy Films…………………………… Y. Nakamura, M. Ohtake, T. Kawai, M. Futamoto, F. Kirino, and N. Inaba

136

Magnetism and Astronomical Infrared Spectrum of Fullerene C60 and Void Induced Graphene Molecules……………………………………………………………………… N. Ota, A. Li, L. Nemes, and M. Otsuka

Board of Directors of The Magnetics Society of Japan
President:
S. Sugimoto
Vice Presidents:
Y. Takemura, J. Hayakawa
Directors, General Affairs:
H. Saito, H. Yuasa
Directors, Treasurer:
H. Takahashi, A. Yamaguchi
Directors, Planning:
T. Kondo, M. Mizuguchi
Directors, Editorial:
T. Kato, S. Yabukami
Directors, Public Relations:S. Sakurada, K. Kakizaki
Directors, International Affairs:
H. Yanagihara, H. Kikuchi
Specially Appointed Director, Gender Equality:
F. Akagi
Specially Appointed Director, Societies Collaborations: K. Fujisaki
Specially Appointed Director, International Conferences: Y. Miyamoto
Auditors:
Y. Takano, K. Kobayashi

142

INDEX
J. Magn. Soc. Jpn., 45, 136-141 (2021)<Paper>Influence of B Content on the Magnetostrictive Propertiesof Single-Crystalline, Poly-Crystalline, and Amorphous Fe-Co-B Alloy Films
Yuta Nakamura1, Mitsuru Ohtake1, Tetsuroh Kawai1, Masaaki Futamoto1,
Fumiyoshi Kirino2, and Nobuyuki Inaba3
Faculty of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan1

Graduate School of Fine Arts, Tokyo University of the Arts, 12-8 Ueno-koen, Taito, Tokyo 110-8714, Japan
Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jyonan, Yonezawa, Yamagata 992-8510, Japan2

3(Fe0.7Co0.3)100–xBx (x = 0–15, at. %) alloy films of 100 nm thickness are prepared on VN(001) single-crystalline
underlayers at 600 °C and on VN poly-crystalline underlayers at room temperature (RT). A high substratetemperature of 600 °C is used to promote epitaxial film growth on VN(001) underlayer. Influences of B content on
the structural, magnetic, and magnetostrictive properties are investigated. The films formed on VN(001) underlayers
involve bcc(001) epitaxial crystalline phase, whereas those formed on VN poly-crystalline underlayers consist ofpoly-crystalline and/or amorphous phases. Surface roughness of film formed on VN(001) underlayer at 600 °C
increases with increasing the B content, whereas flat surfaces are realized for the films formed on VN
poly-crystalline underlayers at RT. The surface morphology is influenced by both the substrate temperature and the
B content. The films with flat surfaces show good soft magnetic properties. In contrast, rough surface causes anincrease in the saturation magnetic field. In the case of films formed on VN(001) single-crystalline underlayer at
600 °C, magnetostriction value of λ100 increases from +200 × 10–6 to +310 × 10–6, as the B content increases from x =0 to 5. With further increasing the B content, λ100 value decreases due to unsaturation of magnetization at amagnetic field of 1200 Oe which is the maximum value used for measurement. λ111 values are nearly zero(– 1 0 × 1 0 – 6 – +20 × 10–6) for all the investigated B contents. Slight addition of B atoms around 5 at. % is effectivein enhancing the λ100 value, while keeping high crystallographic quality, flat surface, and soft magnetic property. On
the contrary, the films formed on VN poly-crystalline underlayers at RT show moderately large λ values of about +60
× 10–6 for all the B contents. The present study shows that control of B content and realization of flat surface areimportant factors in enhancing the magnetostriction of Fe-Co-B film.
Keywords: Fe-Co-B alloy, single-crystal, poly-crystal, amorphous, thin film, magnetostriction
1.

Intr oduc tion

Fe-Co alloys have recently attracted much attention
as one of magnetostrictive materials, since they show
large saturation magnetization (Ms) values1) of about
1920 emu/cm3, low magnetocrystalline anisotropy
energies2) around 0 erg/cm3, and large magnetostriction(λ) values3)–7) of +100 × 10–6 – +250 × 10–6 by
optimizing the composition. Furthermore, it has beenreported that large λ values of +150 × 10–6 – +250 × 10–6
can be obtained in poly-crystalline Fe-Co films with Co
contents of 35–75 at. % prepared by deposition at room
temperature (RT) followed by annealing at 800 °C8).
In order to determine the magnetostriction values
along <100> and <111>, λ100 and λ111, it is required toprepare single-crystalline samples. Epitaxial films are
candidates for such purpose. In our previous study9),
Fe-Co single-crystalline films were prepared on
MgO(001) substrates at 300 °C by varying the Cocontent from 0 to 50 at. %. λ100 value increased withincreasing the Co content. λ100 values larger than+230 × 10–6 were observed for the films with Co
content higher than 30 at. %. The λ111 value of Fe70Co30
film was nearly zero.
In order to obtain a good soft magnetic property, it
seems useful to control the Co content to be around
Corresponding author:
Mitsuru Ohtake (e-mail: ohtake-mitsuru-yt@ynu.ac.jp).

13630–40 at. %, because the magnetocrystalline anisotropy
energy is almost zero. Furthermore, B is often added to
Fe-Co alloy to improve the soft magnetic property. The
magnetostrictive properties of Fe-Co-B alloys have beenstudied by using film10)–13) and ribbon14)–15) samples
consisting of poly-crystalline or amorphous phase. Thereis a possibility that B atom addition may enhance themagnetostriction, similar to the case of Fe-B alloy.
However, there are no reports on systematicalinvestigation on magnetostrictive properties by using
single-crystalline, poly-crystalline, and amorphous
specimens.
The purpose of present study is to prepare
single-crystalline, poly-crystalline, and amorphous(Fe0.7Co0.3)100–xBx films with different B contents and toinvestigate the magnetostrictive properties. In thepresent study, (Fe0.7Co0.3)100–xBx films are formed on
VN(001) single-crystalline underlayers at 600 °C for
preparation of single-crystalline (Fe0.7Co0.3)100–xBx films.
A high substrate temperature of 600 °C is used topromote epitaxial growth on VN(001) underlayer.
(Fe 0 . 7 Co 0 . 3 ) 1 0 0 – x B x films are also formed on VN
poly-crystalline underlayers at RT for preparation ofpoly-crystalline and/or amorphous (Fe0.7Co0.3)100–xBx
films. When growth of a film on an underlayer follows
the Volmer-Weber mode16), the film consists of islands.
The contact angle of island with respect to theunderlayer is influenced by the combination of surface
energies of film and underlayer (Young’s relation). In

Journal of the Magnetics Society of Japan Vol.45, No.6, 2021

INDEX

10

15

(c-1)

(d-1)

(i-1)

004

RHEED

(b-1)

_

(d-3)

(002) bcc

112

112

112

112

002

112

_

40

112

Fe-Co-B

(d-2)

002

002

MgO
(002)

_

_

112

_

112

(c-2)

002

_

112

(b-2)

002

_

(a-2)

_

Intensity (a. u.)

112_(Fe0.7Co0.3)100–xBx/
VNsingle-crystal(a-1)

B content, x (at. %)60

80

MgO(004)

5

_

0

100

(e)

(f)

(g)

(h)

(i-2)

RHEED

(Fe0.7Co0.3)100–xBx/
VNpoly-crystal

Diffraction angle, 2θ (deg.)

Fig. 1 [(a-1)–(d-1), (e)–(h)] RHEED patterns observed for (Fe0.7Co0.3)100–xBx films of 100 nm thickness with x = [(a-1),(e)] 0, [(b-1), (f)] 5, [(c-1), (g)] 10, and [(d-1), (h)] 15 formed (a-1)–(d-1) on VN(001) single-crystalline underlayers at
600 °C and (e)–(h) on VN poly-crystalline underlayers at RT. (a-2)–(d-2) Line profiles measured along the dottedlines in RHEED patterns of (a-1)–(d-1), respectively. (d-3) XRD pattern measured for the (Fe0.7Co0.3)100–xBx film withx = 15 formed on VN(001) single-crystalline underlayer. (i) Schematic diagrams of RHEED patterns simulated for(i-1) (001) single-crystalline and (i-2) poly-crystalline surfaces with bcc structure. The incident electron beam isparallel to (a-1)–(d-1) VN[100] (|| MgO[100]) or (i-1) bcc[110].
order to suppress the surface undulation, it is useful toemploy an underlayer material whose surface energy islarger than that of film material. The surface energy ofVN crystal (2.7 J/m2)17) is higher than that of Fe crystal(2.2 J/m2)18), though there are, to our knowledge, noreports on the surface energy of Fe70Co30 crystal.
Introduction of VN underlayer seems effective to realize
flat film surface, similar to the case of Fe50Pt50 film on
VN underlayer19). VN underlayers are thus introducedin the present study.
2.

Experimental Procedure

A radio-frequency (RF) magnetron sputteringsystem with the base pressure lower than 4 × 10–7 Pa
was used for film formation. The distance between
target and substrate and the Ar gas pressure during
sputtering were respectively fixed at 150 mm and 0.67
Pa. (Fe0.7Co0.3)100–xBx (x = 0, 5, 10, and 15 at. %) and VN
alloy targets of 3 inch diameter were employed and therespective RF powers were adjusted to 51, 90, 56, 60,
and 96 W to make the deposition rate 0.02 nm/s for all
the materials. The film compositions were confirmed byenergy dispersive X-ray spectroscopy (EDS) and X-ray
photoelectron spectroscopy (XPS) and the errors wereless than 1.5% from the target compositions.
VN(001) single-crystalline underlayers of 10 nm
thickness with B1 structure were prepared throughhetero-epitaxial growth on MgO(001) substrates of 300
μm thickness in the orientation relationship ofwhereasVN
VN(001)[100]||MgO(001)[100]19),
poly-crystalline underlayers of 10 nm thickness wereformed on thermally oxidized Si substrates of 350 μm
thickness.
The
substrate
temperatureduringunderlayer formation was kept constant at 600 °C for
both cases. The arithmetical mean surface roughness(Ra) values of VN single- and poly-crystalline

underlayers measured by atomic force microscopy(AFM) were lower than 0.1 nm. Then, (Fe0.7Co0.3)100–xBx
films of 100 nm thickness were formed on the VN(001)underlayers at 600 °C and on the VN poly-crystal
underlayers at RT.
The structure was studied by reflection high-energy
electron diffraction (RHEED) and X-ray diffraction(XRD) with Cu-Kα radiation (wavelength: 0.15418 nm).
The surface morphology was observed by AFM. The
magnetization curves were measured by vibrating
sample magnetometry (VSM). The magnetostriction was
evaluated by using a cantilever method under rotating
magnetic fields up to 1200 Oe. The relative lengthvariation, Δ l / l , was calculated from the following
formula,Δll=

ΔS ts2 Es (1 + νf)

3 L2 tf Ef (1 – νs) ,(1)

where ΔS is the measured bending, L is the distance
between laser beam points (12.5 mm), t is the thickness,
E is the Young’s modules, ν is Poisson’s ratio, and thesubscript of s or f respectively refers to substrate or film.
The details of our measurement system and calculation
are reported in our previous papers9),20).
3.

Resu lts an d Disc u ssion

3.1

Str u c tu r e
The structures of (Fe 0.7 Co 0.3 ) 100– x B x films withdifferent B contents prepared on VN single- andpoly-crystalline underlayers were studied by RHEED.
Figures 1(a-1)–(d-1) show the RHEED patterns
observed for (Fe0.7Co0.3)100–xBx films of 100 nm thickness
formed on VN(001) single-crystalline underlayers at
600 °C. A diffraction pattern from bcc(001)single-crystalline surface is recognized for the film withx = 0 (Fig. 1(a-1)), as shown in the schematic diagram of

Journal of the Magnetics Society of Japan Vol.45, No.6, 2021

137

INDEX

B content, x (at. %)
10
29 nm
0

(b-1)

15
69 nm
0

(c-1)

(e-1)

102 nm
0

(d-1)

0
100
0
1000
(a-2)

2000

1000
35 nm
0

0

0

0

0 10000 10000 1000

(b-2)

2000

1000
27 nm
0

(c-2)

2000

1000
16 nm
0

(d-2)

2000

1000

0

6 nm
0

0
100
0
1000
2000

1000

0

0

0
0 10002000

1000

0 10002000

1000

Distance (nm)

0 1000
2000

1000

0

Arithmetical mean surface roughness, Ra (nm)single-crystal
poly-crystal(Fe0.7Co0.3)100–xBx
VN /

5
5 nm
0

(a-1)

Thickness (nm)(Fe0.7Co0.3)100–xBx
VN /

0

100
10
1
0.1
0

(e-2)

10

100
10
1
0.1
0
10
B content, x (at. %)Fig. 2 (a)–(d) AFM images observed for (Fe0.7Co0.3)100–xBx films of 100 nm thickness with x = (a) 0, (b) 5, (c) 10, and(d) 15 formed (a-1)–(d-1) on VN(001) single-crystalline underlayers at 600 °C and (a-2)–(d-2) on VN poly-crystalline
underlayers at RT. (e) B content dependences of Ra values of (Fe0.7Co0.3)100–xBx films formed (e-1) on VN(001)single-crystalline underlayer at 600 °C and (e-2) on VN poly-crystalline underlayer at RT.
Fig. 1(i-1). A single-crystalline Fe70Co30(001) film is
epitaxially grown on the VN underlayer. The
crystallographic orientation relationship is determinedas (Fe0.7Co0.3)100–xBx(001)[110] || VN(001)[100]. A
diffraction pattern from bcc(001) surface is also
observed for the film with x = 5 (Fig. 1(b-1)). However
when the B content increases up to x = 10 (Fig. 1(c-1)),ring-like and halo patterns are overlapped. The result
suggests that the film with x = 10 involves
poly-crystalline and amorphous phases in addition tobcc(001) crystalline phase. With further increasing the
B content to x = 15 (Fig. 1(d-1)), the RHEED pattern ismore blurred, though the reflection spots from bcc(001)surface are still appearing as shown in the line profile of
RHEED pattern of Fig. 1(d-2). The existence of bcc(001)crystalline phase is also confirmed by XRD, as shown in
Fig. 1(d-3). These results indicate that the volume ratioof amorphous to crystalline phase has increased.
Although the crystallographic quality deteriorates withincreasing the B content, (Fe0.7Co0.3)100–xBx films
including bcc(001) crystalline phase are obtained for all
the investigated B contents.
Figures 1(e)–(h) show the RHEED patterns
observed for (Fe0.7Co0.3)100–xBx films of 100 nm thickness
formed on VN poly-crystalline underlayers at RT. A
diffraction pattern from bcc poly-crystalline surface isrecognized for the films with x = 0 and 5 (Figs. 1(e), (f)),
as shown in the schematic diagram of Fig. 1(i-2). The
films are composed of bcc poly-crystalline phase. Whenthe B content increases to x = 10 (Fig. 1(g)), a halo
pattern is overlapped with a ring-like pattern. The filmwith x = 10 consists of a mixture of poly-crystalline andamorphous phases. Only a halo pattern is appearing forthe film with x = 15 (Fig. 1(h)). Amorphous film isformed at the B content of x = 15. B content dependenceofcrystallizationissimilarbetweenthe(Fe0.7Co0.3)100–xBx films formed on single- andpoly-crystalline underlayers. In detail, however,138

amorphous phase formation is more pronounced for thefilms formed on VN poly-crystalline underlayers, which
are prepared at a lower substrate temperature of RT.
3.2

Su r f ac e mor ph olog y an d mag n etic pr oper ty
Surface morphologies, which influence themagnetization properties, were observed by AFM.
Figures 2(a-1)–(d-1) show the AFM images observed for(Fe0.7Co0.3)100–xBx films formed on VN single-crystalline
underlayers at 600 °C. Figure 2(e-1) summarizes the B
content dependence of Ra. For the film with x = 0 (Fig.
2(a-1)), a flat surface with the Ra value of 0.4 nm is
realized, even though a high substrate temperature of
600 °C is used. However with increasing the B content,
wettability of (Fe0.7Co0.3)100–xBx film with respect to VN
underlayer gradually deteriorates (Figs. 2(b-1)–(d-1)).
Ra value increases to 13 nm with increasing the B
content to x = 15. For the film with x = 0, employment of
VN underlayer with high surface energy (2.7 J/m2)17) isapparently effective in reducing the surface roughness,similar to the case of Fe50Pt50 film19). The reason for Ra
increase with B addition is attributed to an increase of
surface energy of (Fe0.7Co0.3)100–xBx alloy material, whichis expected from the cases of Ti-B21),22) and V-B21),23)
alloys. The contact angle between the film and the VN
underlayer materials is considered to have increased
and the surface roughness is thus enhanced.
Figures 2(a-2)–(d-2) and (e-2), respectively, show
the AFM images and the Ra values of (Fe0.7Co0.3)100–xBx
films formed on VN poly-crystal underlayers at RT.
These films have flatter surfaces, when compared withthose of (Fe0.7Co0.3)100–xBx films formed on VN(001)underlayers. The difference is possibly due to the effectof lower deposition temperature of RT. Furthermore, it
is noted that lower Ra value is realized with increasing
the B content, which is interpreted to be corresponding
to the structural variation from crystalline toamorphous phase.

Journal of the Magnetics Society of Japan Vol.45, No.6, 2021

INDEX

B content, x (at. %)

(b-1)

0

15

(c-1)

(d-1)

–1

0

1

–2

2000 (a-2)

0

0

2 –2

(b-2)

2

(c-2)

–2

0

2

(d-2)

–2

0

2 –2

0

2 –2

0

2 –2

0

2

0

100
0

(e-2)

1000

–2000

Hc[100]

0

2000

0

200

Ms

Hc[110]

1000

[100]
[110]

–2000

(e-1)

2000

Ms
Hc

0

10

Coercivity, Hc (Oe)10

Saturation magnetization, Ms (emu/cm3)

single-crystal
poly-crystal(Fe0.7Co0.3)100–xBx
VN /5

2000 (a-1)

Magnetization, M (emu/cm3)(Fe0.7Co0.3)100–xBx
VN /

0

200
100
0

B content, x (at. %)Magnetic field, H (kOe)

Fig. 3 (a)–(d) In-plane magnetization curves measured for (Fe0.7Co0.3)100–xBx films of 100 nm thickness with x = (a) 0,(b) 5, (c) 10, and (d) 15 formed (a-1)–(d-1) on VN(001) single-crystalline underlayers at 600 °C and (a-2)–(d-2) on_ VN
poly-crystalline
underlayers at RT. The magnetic field is applied parallel to (Fe0.7Co0.3)100–xBx[100] (|| VN[110] ||_MgO[110]) or (Fe0.7Co0.3)100–xBx[110] (|| VN[100] || MgO[100]). (e) B content dependences of Ms and Hc values of(Fe0.7Co0.3)100–xBx films formed (e-1) on VN(001) single-crystalline underlayer at 600 °C and (e-2) on VN
poly-crystalline underlayer at RT.
Figures3(a-1)–(d-1)
show
thein-planemagnetization curves of (Fe0.7Co0.3)100–xBx films
involving bcc(001) crystalline phase prepared on VN
single-crystalline underlayers. The magnetic field isapplied parallel to [100] or [110] direction. The film withx = 0 is easily magnetized when the magnetic field isapplied parallel to [100], whereas the magnetization
curve measured along [110] saturates at a higher
magnetic field (Fig. 3(a-1)). The magnetization behavior
is reflecting the magnetocrystalline anisotropy of bulk
bcc-Fe70Co30 crystal with the easy magnetization axes
parallel to <100>5). On the contrary, the films including
B atoms (x = 5–15) show nearly isotropic in-planemagnetic properties (Figs. 3(b-1)–(d-1)). The reason isconsidered to be partly due to reduction inmagnetocrystalline anisotropy energy and structuralvariation from crystalline to amorphous caused by B
addition and partly due to increase in surface roughness
which is shown by AFM observation (Figs. 2(b-1)–(d-1)).
Figure 3(e-1) shows the B content dependences of Ms
and coercivity (Hc) measured for (Fe0.7Co0.3)100–xBx film
formed on VN(001) single-crystalline underlayer. With
increasing B content, Ms is decreasing, while Hc isincreasing. The increase in Hc is attributable to theenhancement of surface roughness that prevents themagnetic domain wall motion.
Figures3(a-2)–(e-2)
showthein-planemagnetization curves and the Ms and Hc values of(Fe0.7Co0.3)100–xBx films consisting of poly-crystalline
and/oramorphous
phasespreparedon
VN
poly-crystalline underlayers. As the B content increases,
Ms value decreases, similar to the case of(Fe0.7Co0.3)100–xBx films formed on VN(001) underlayers.
On the contrary, Hc value decreases with increasing the
B content, which is different from the case of films
formed on VN(001) underlayers. The reduction in Hc
seems to be related with the decrease in Ra and thestructural variation from crystalline to amorphous
phase.

M ag n e t o s t r i c t i v e p r o p e r t i e s
Magnetostrictive behaviors were investigated byusing a cantilever method under in-plane rotating
magnetic fields. The relative length variations ofbcc(001) single-crystal along [100] and [110], Δl/l[100](φ)
and Δ l / l [110](φ), under an in-plane rotating magnetic
field are respectively shown9) as

3.3

Δl
l
Δl

[100](φ) =343λ100 cos2φ +141

λ100 ,(2)λ100 ,λ111 sin2φ +(3)[110](φ) =l44where φ is the angle of magnetic field direction withrespect to [100]. Δl/l[100](φ) and Δl/l[110](φ) are cosine andsine waves, whose phases vary depending on the signsof λ100 and λ111 and whose amplitudes correspond to theabsolute values of 3/4 times λ100 and λ111, respectively.
Figure 4 shows the Δl/l[100](φ) and Δl/l[110](φ) measuredfor (Fe0.7Co0.3)100–xBx films including bcc(001) crystalline
phase prepared on VN(001) underlayers. The
amplitudes of Δl/l[100](φ) are fairly larger than those of
Δ l / l [110](φ) for the respective B contents. The result
suggests that the films possess large λ100 and small λ111.
The phases of Δl/l[100](φ) correspond to positive λ100 for
all the B contents. On the other hand, the phase of
Δ l/ l [110](φ) is different between the films without andwith B atoms. The signs of λ111 of films with x = 0 and
5–15 are respectively negative and positive.
The relative length variation of poly-crystalline
and/or amorphous phase, Δ l / l poly-crystalline/amorphous(ψ), isshown asΔlpoly-crystalline/amorphous(ψ)
l
(4)
3
1
λpoly-crystalline/amorphous cos2ψ +=λpoly-crystalline/amorphous ,44where λpoly-crystalline/amorphous is the magnetostriction valueand ψ is the angle of magnetic field direction withrespect to the direction rotated by 45° from the

Journal of the Magnetics Society of Japan Vol.45, No.6, 2021

139

INDEX

Relative length variationΔl/l (φ)

B content, x (at. %)
0
(a)

5

10

(b)

[100]
[110]

15

(c)

(d)

100×10–6

0

90

180

270

360 0

90

180

270 360 0
90 180
Rotation angle, φ (deg.)

270

360 0

90

180

270

360

Fig. 4 Δl/l[100](φ) and Δl/l[110](φ) under a rotating magnetic field of 1200 Oe measured for (Fe0.7Co0.3)100–xBx films of
100 nm thickness with x = (a) 0, (b) 5, (c) 10, and (d) 15 involving bcc(001) crystalline phase prepared on VN(001)underlayers. The observation direction is parallel to [100] or [110] of the bcc(001) crystal.

Relative length variation
Δl/lpoly-crystalline/amorphous (ψ)

B content, x (at. %)
0

5

(a)

10

(b)

15

(c)

(d)

100×10–6

0

90

180

270

360 0

90

180

270 360 0
90 180
Rotation angle, ψ (deg.)

270

360 0

90

180

270

360

Fig. 5 Δl/lpoly-crystalline/amorphous(ψ) under a rotating magnetic field of 1200 Oe measured for (Fe0.7Co0.3)100–xBx films of
100 nm thickness with x = (a) 0, (b) 5, (c) 10, and (d) 15 consisting of poly-crystalline and/or amorphous phases
prepared on VN poly-crystalline underlayers.

B content, x (at. %)Magnetostriction value, λ(×10–6)
300

0

5

(a)

λ100

λ111

10

(b)

λpoly-crystalline/amorphous

15

(c)

(d)

200
100
0
–100

0

500

1000

0

500

1000
0
500
Magnetic field, |Hrot| (Oe)

1000

0

500

1000

Fig. 6 Magnetic field dependences of λ100, λ111, and λpoly-crystalline/amorphous measured for (Fe0.7Co0.3)100–xBx films of 100
nm thickness with x = (a) 0, (b) 5, (c) 10, and (d) 15.
observation
direction.
Figure5shows
theΔl/lpoly-crystalline/amorphous(ψ) measured for (Fe0.7Co0.3)100–xBx
films composed of poly-crystalline and/or amorphous
phases prepared on VN poly-crystalline underlayers.
The amplitudes of Δl/lpoly-crystalline/amorphous(ψ) are smaller
than those of Δ l / l [100](φ) and larger than those ofΔl/l[110](φ).
Figure 6 shows the magnetic field dependences of
λ100, λ111, and λpoly-crystalline/amorphous. The λ100 and λ111
values of film with x = 0 almost saturate at a low
magnetic field of 25 Oe. The λ100 and λ111 values of filmwith x = 15 do not saturate at a magnetic field of 1200
Oe. On the other hand, the λpoly-crystalline/amorphous of films
with x = 0–15 saturate at low magnetic fields around
25–50 Oe. The saturation behaviors of magnetostriction

140

are consistent with those of magnetization which are
shown in Fig. 3.
Figure 7 summarizes the B content dependences of
λ100, λ111, λcal, and λpoly-crystalline/amorphous measured under arotating field of 1200 Oe. Here, λcal, which is given as

2

3

(5)
λ111 ,
5
5
is the approximate magnetostriction value of isotropic
material calculated by using λ100 and λ111. The film withx = 0 consisting of bcc(001) single-crystalline phaseshows a large λ100 value of +200 × 10–6, similar to thecase of Fe70Co30 film epitaxially grown on MgO(001)9).
λ100 value increases to +310 × 10–6 by B atom addition of
x = 5. With further increasing the B content, λ100 value
begins to decrease. The result is considered to be partly
λcal =λ100 +

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INDEX(

nearly zero (–10 × 10–6 – +20 × 10–6) for all theinvestigated B contents. The films consisting ofpoly-crystalline and/or amorphous phases show
moderately large λ values of about +60 × 10–6 for all the
B contents. The present study has shown that B
addition as well as realization of flat surface areimportant factors in enhancing the magnetostriction.

10–6)

Magnetostriction, λ

300

λ100

200
λcal

100

λpoly-crystalline/amorphous

0

–100

λ111
0

5
10
B content, x (at. %)15

Fig. 7 B content dependences of λ100, λ111, λcal, andλpoly-crystalline/amorphous under a rotating field of 1200 Oe
measured forthickness.

(Fe0.7Co0.3)100–xBx

films

of

100

nm

due to unsaturation of magnetization at 1200 Oe andpartly due to deterioration of magnetostriction causedby rough surface. λ111 value increases from a small
negative value of –10 × 10–6 to a small positive value of+20 × 10–6 with increasing the B content from x = 0 to 5
and then stays almost constant from x = 5 to 15. As aresult, a maximum value of λcal is recognized at x = 5. In
contrast, the films composed of poly-crystalline and/or
amorphous phases have similar λpoly-crystalline/amorphousvalues of around +60 × 10–6 for all the B contents. These
results indicate that λ100 value of bcc(001) crystal does
not decrease in the B content range of x = 0–15. It
seems possible to prepare an (Fe0.7Co0.3)100–xBx film withlarger λ100 value with the B content higher than x = 10
by reducing the surface roughness which may yield low
Hc. The present study shows that B atom addition iseffective in enhancing λ100 value and that it is importantto prepare a thin film with reduced surface undulationin order to extract the intrinsic magnetostrictive
property.
4.

Conclusion(Fe0.7Co0.3)100–xBx (x = 0–15, at. %) alloy films of 100
nm
thicknessarepreparedon
VN(001)single-crystalline underlayers at 600 °C and on VN
poly-crystalline underlayers at RT. Single-crystalline
films of bcc(001) orientation are obtained on VN
single-crystalline underlayers, whereas poly-crystalline
and/or amorphous films are formed on VN
poly-crystalline underlayers, where the structure varies
depending on the B content and the deposition
Ra, oftemperature.
The
surfaceroughness,single-crystalline film increases from 0.4 to 13 nm withincreasing the B content from x = 0 to 15, while
poly-crystalline and/or amorphous films possess flattersurfaces with the Ra lower than several nanometers.
Good soft magnetic properties are observed for the films
with flat surfaces, and surface roughness is shown to be
an origin in increasing the coercivity. The
single-crystalline film with x = 0 shows a large λ100
value, which is enhanced by B addition of x = 5 up to+310 × 10–6. As the B content further increases, the λ100
value decreases due to unsaturation of magnetizationand increase in surface roughness. The λ111 values areThis paper is based on results
Acknowledgements
obtained from a project, 20002152-0, subsidized by the
New Energy and Industrial Technology Development
Organization. Authors thank Mr. Naoki Yoshihara and
Ms. Yuko Kaneda of Instrumental Analysis Center at
Yokohama National University for their excellent
technical supports for EDS, XPS, and XRD
measurements.
References
1) R. M. Bozorth: Ferromagnetism, p. 194 (Van Nostrand, New York,1964).
2) S. Chikazumi: Physics of Ferromagnetism, p. 111 (Syokabo, Tokyo,
1961).
3) H. M. A. Urquhart, K. Azumi, and J. E. Goldman: DTIC Tech. Rep.,
no. AD0018771 (1953).
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Sasaki, T. Sekiguchi, and S. Yamaura: Mater. Trans., 55, 556(2014).
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Hattrick-Simpers, R. Suchoski, R. Takahashi, M. L. Young, A.
Mehta, L. A. Bendersky, S. E. Lofland, M. Wuttig, and I. Takeuchi:Nat. Commun., 2, 518 (2011).
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Inaba: J. Magn. Soc. Jpn., 43, 50 (2019).
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App. Phys., 97, 10C906 (2005).
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Ruffoni, and S. Pascarelli: Phys. Rev. B, 85, 134437 (2012).
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Jpn. J. Appl. Phys., 44, L587 (2005).
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Kussbach, and P. Allia: Phys. Rev. B, 63, 094427 (2001).
15) J. P. Sinnecker, R. S. Turtelli, R. Grössinger, G. Badurek, P. Riedler,
and S. Menhart: J. App. Phys., 85, 1043 (1999).
16) J. A. Venable: Introduction to surface and thin film process(Cambridge Univ. Press, New York, 2000).
17) R. Nakanishi, S. Kunitsugu, and K. Sueoka: J. Surf. Finish. Soc.
Jpn., 61, 535 (2010).
18) L. Vitos, A. V. Ruban, H. L. Skriver, and J. Kollár: Surf. Sci., 411,
186 (1998).
19) T. Shimizu, M. Ohtake, M. Futamoto, F. Kirino, and N. Inaba: J.
Magn. Soc. Jpn., 43, 109 (2019).
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8429 (2011).
21) M. Aldén, H.L. Skriver, S. Mirbt, and B. Johansson: Surf. Sci., 315,
157 (1994).
22) E. N. Eremin, V. M. Yurov, V. Ch. Laurynas, S. A. Guchenko, andS. S. Kasymov: J. Phys.: Conf. Ser., 1210, 012041 (2019).
23) S. Ma, N. Zong, H. Dong, and T. Jing: IOP Conf. Ser.: Mater. Sci.
Eng., 861, 01204 (2020).
R e c e i v e d M a r . 3 1 , 2 0 2 1 ; R e v i s e d J ul . 9 , 2 0 2 1 ; A c c e p t e d S e p . 1 6 , 2 0 2 1

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J. Magn. Soc. Jpn., 45, 142-148 (2021)<Paper>Magnetism and Astronomical Infrared Spectrum of
Fullerene C60 and Void Induced Graphene Molecules
Norio Ota1, Aigen Li2, Laszlo Nemes3 and Masaaki Otsuka4
1-1-1 Tennodai, Tsukuba-City Ibaraki, 305-8571, Japan
Columbia, MO 65211, USA,
3Research Center for Natural Sciences, Ötvös Lóránd Research Network, Budapest 1519, Hungary
4Okayama Observatory, Kyoto University, Asakuchi Okayama, 719-0232, Japan.

1Graduate school of Pure and Applied Sciences, University of Tsukuba,

2Department of Physics and Astronomy, University of Missouri,

Fullerene C60 shows astronomical four infrared bands (IR) of carbon rich planetary nebulae. However, there remain
many unidentified bands. Our previous paper revealed that single void-defect induced graphene molecule reproduce
many astronomical bands. In this paper, we investigated a series of multiple-void induced graphene molecules. We
tried spin dependent DFT calculation. Model molecules are C23 (one carbon pentagon ring among hexagon network),
C22 (two), and C21 (three). Those were all magnetic molecules with spin state of Sz =2/2, 2/2 and 4/2 respectively.
Calculated IR was compared with astronomical observation. The largest astronomical band at 18.9 micrometer was
found in C23. Second largest band at 17.4 micrometer appeared both in C22 and C21. Other major bands from 6 to 10
micrometer were reproduced well by a combination of C23, C22 and C21. Similarly, larger size graphene molecules of C53,
C52 and C51 were also magnetic and reproduced astronomical bands as well. Weighting sum IR of those molecules
could successfully trace astronomical 12 bands from 6 to 20 micrometer. A series of multiple void induced graphenewould be major component of astronomical carbon. Fullerene C60 would be one of them.
Key words: graphene, fullerene C60, spin state, DFT, infrared spectrum

1. Introduction
It is well known that fullerene C60 1) shows
astronomical infrared bands (IR). In 2010, Cami et al.2)
reported the presence of C60 in astrophysicalenvironments by the detection of a set of four bands at
7.0, 8.45, 17.3 and 18.9 μm. Many studies are followingit 3)- 8). Typical astronomical objects are the Galactic
planetary nebula Tc1 2) and the Small Magellanic Cloudnebula Lin49 9). Observed spectra were 12 bands, whichwere compared with experiment and theory 10)- 12). Thereremain many unidentified bands not explained by C60.
It is also well known that graphene is a raw material forsynthesizing fullerene 13), 14). Otsuka et al.9) suggested
the presence of small graphene in space. Graphene wasexperimentally synthesized by Geim and Novoselov 15).
Our recent study on graphene molecule by the density
functional theory (DFT) shows that single void-defect on
carbon hexagon network brings highly polarized spin
configuration and structure change 16), 17), and finallybrings drastic change of molecular vibrational IR. Such
result was understood based on pure carbon
magnetism 18)- 24). Model molecules were C23 and C53,
which has one carbon pentagon ring among hexagons. It
was firstly revealed that calculated IR shows goodcoincidence with astronomically observed one. Also,
calculation show rough coincidence with the laser
induced carbon plasma experiment 25)- 28).
________________________________________________
Corresponding author: Norio Ota (n-otajitaku@nifty.com).

142

Those molecules were magnetic with spin-state ofSz =2/2. Calculated IR of C23 and C53 could reproduce
astronomically observed one of carbon rich nebulae Tc1
and Lin49. However again, there remain someunidentified bands, especially second largest band at
17.4 μm. We should do advanced study on nano-carbon
candidates.
Here is an interesting idea that we should study
multiple void induced graphene molecules, because
fullerene C60 has 12 carbon pentagon rings combinedwith 20 hexagons. Such multiple pentagon rings could
be induced from multiple voids on graphene sheet. In
2013, Tielens opened such concept under the name of
top-down-process in his review article 29). In this study,
we investigate a series of multiple void induced
graphene molecules focusing on spin-state andmolecular vibrational IR. Results will be compared withastronomical observation and laboratory experiment.
This paper is a joint study by different research field,
which would develop a new science field named as likethe Astro-magnetism.

2. Calculation Method
In calculation, we used DFT 30), 31) with theunrestricted B3LYP functional 32). We utilized theGaussian09 software package 33) employing an atomic
orbital 6-31G basis set. Unrestricted DFT calculation
was done to have the spin dependent atomic structure.
The required convergence of the root-mean-squaredensity matrix was 10−8. Based on such optimized

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molecular configuration, fundamental vibrationalmodes were calculated, such as carbon to carbon (C-C)
stretching modes, (C-C) bending modes and so on, using
the same Gaussian09 33). This calculation also gives
harmonic vibrational frequency and intensity ininfrared region. The standard scaling is applied to thefrequencies by employing a scale factor of 0.975 for purecarbon system taken from the laboratory experimental
value of 0.965 based on coronene-molecule of C24H12 34).
Correction due to anharmonicity was not applied to
avoid uncertain fitting parameters. To each spectral line,
we assigned a Gaussian profile with a full width at half
maximum of 4cm−1. Any molecular symmetricity was
not applied to compare delicate change of molecularconfiguration and compare small difference of totalenergy.

3. Fullerene C60 and Graphene C23
3.1 Stable spin state

Input parameters for DFT are charge and spinparameter Sz. Charge was zero (neutral) for every case.
We dealt total molecular spin S (vector). Molecule isrotatable material, easily follows to the external
magnetic field of z-direction. Projected component Sz to
z-direction is a good quantum number.
Result of C60 is illustrated in Fig. 1. Total molecularenergy of Sz =0/2 is 1.79 eV lower than that of Sz =2/2.
Stable spin-state was nonmagnetic one of Sz =0/2,
which is contrary to previously reported graphenemolecule of C23 16) with magnetic Sz =2/2. We note again
here the creation step of C23. As illustrated in Fig. 2,
starting molecule was C24 having seven carbon hexagon
rings. High-speed particle may attack one carbon atom
and kick it out. Single void will be created. There occurs
re-bonding between carbon atoms. Resulted molecule
was C23 having one pentagon ring. Initial void-defectholds 3 radical carbons and allows 6 spins. Six spins
make capable spin-states of Sz =0/2, 2/2, 4/2 and 6/2.
Among them, calculated energy of Sz =4/2 and 6/2 show
unstable high energy. Here, we should compare Sz =0/2
and 2/2. It should be noted that molecular energy ofSz =2/2 was 0.64 eV lower (stable) than Sz =0/2. We cansee up-spin major spin cloud for Sz =2/2 as illustrated
on bottom right of Fig. 2 at a cutting surface of spin
density 10 e/nm3. We can see up-spin cloud (by red) at a
pentagon site.

marked by blue arrows on middle. Calculated spectrumof C60 was illustrated for Sz =0/2 by green and for Sz=2/2 by light green. It should be noted that the observed
spectra are seen in emission, while DFT gives
absorption. A star may illuminate the molecule andexcites them to give rise infrared emission. Detailed
discussion was done by Li and Drain 35), 36). We regard
that DFT calculated absorbed spectrum is a mirror
image of emission one in case of sufficient high energy
excitation.
Calculated spectrum of Sz =2/2 of C60 shows so
ambiguous as illustrated on bottom of Fig. 3. Whereas
for stable spin-state Sz =0/2, we can see specific fourbands.
In Table 1, every IR obtained by experiment,
astronomical observation and DFT calculation werelisted in detail. Calculated largest band of C60 is
18.7 μm, which is 0.1 μm shorter than gas-phaselaboratory
experimentof
18.8 μm.
Whereas,astronomically observed band was 18.9 μm. Thereremains a question that astronomical 18.9 μm band
would come from C60 or not. Because, in our previous
study, single void induced C23 show a band just at 18.9μm.

3.2 Infrared spectrum

Comparison of calculated IR with astronomicallyobserved one is important. Both DFT targeted moleculeand interstellar molecule have common condition, thatis, of ultra-low material density and of low temperature.
Laboratory experiment on earth cannot realize suchconditions. Otsuka et al.9) opened astronomicallyobserved bands as illustrated in Fig. 3 on top for Tc1
nebula by red and for Lin49 by blue. Laboratory
gas-phase experiment for C60 by Nemes et al.26) wasFig. 1 Spin state of fullerene C60 by DFT calculation.

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Table 1 Infrared spectrum of C60 and graphene molecules

In Fig. 4, sharp astronomical emission peak at 18.7
μm (marked by black arrow) is a strong atomic emission
line of SIII. We are afraid that such strong atomic line
may hide a band of C60.
Calculated band of C60 at 17.4 μm coincides well bothwith astronomical Band-B (17.4 μm) and with
gas-phase laboratory experiment at 17.4 μm 26).
In shorter wavelength region, calculated C60 show aband at 6.77 μm. It was 0.2 μm shorter thanexperimental bands of 6.97 μm. Cami et al. suggested
that Band-L at 7.1 μm comes from C60. However, it wasstrange that in our previous paper 16), graphene C23
show just 7.1 μm band. Gas phase experiment also hassome difficulty. Experiment was done at temperaturefrom 850 to 1150 K and simply extrapolated to 0 K,
which has a gap of five order weak strength. Under suchcomplicated situation, we need advanced study.
Cami et al.2) also suggested possibility of fullerene C70.
Astronomical bands would be explained by mixing C 70
and C60. However, bands of C70 were 18.7, 17.3, 15.5 and14.8 μm. They could not explain observed major bands
from 6 to 13 μm.

Fig. 2 Spin state of single void induced graphene C23.

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Fig. 3 Comparison of IR of fullerene C60 by astronomical
observation,
laboratory
experimentandDFT
calculation.
As shown in Fig. 4, we can see many astronomicalbands from Band-A to M. Our previous results 16) areagain illustrated in Fig. 4. Major band of C23 has twin
peaks at 18.9 and 19.0 μm, also C53 has single peak at
18.9 μm, which are just related to observed Band-A.
Second major Band-B was seen at 17.4 μm, which was
reproduced well by calculated C60. However
unfortunately, C23 and C53 show weak intensity at 17.4
μm.
At shorter wavelength region from 6 to 10 μm,
calculated spectrum of C60 only show two bands at
positions of Band-I and M. While graphene C23 and C53
show many bands to coincide well with astronomicalbands of Band-G, H, I, J, K, L and M. Moreover, C53
could reproduce further detailed bands coincide withastronomical Band-D, E, F.

4. Multiple-Void Induced Graphene Molecules
4.1 Stable spin state

Fullerene C60 has 12 carbon pentagon rings among 20
hexagons. Multiple pentagon rings could be realized
from multiple voids. In this study, we assumed multiple
voids for multiple carbon pentagons. We started from
C24 as illustrated in Fig. 5. Single void could induce C23
with one pentagon ring marked by red circled 5.
Two-voids induced C22 has two pentagons. Molecularconfiguration was umbrella like curved structure asshown by side view. Three voids induced C21 also show
umbrella like configuration. Origin of such structure
was discussed by Ota 37) based on re-bonding between
carbon atoms by mixing sp2-orbit with sp3. Also, Galue& Leines 38) discussed the -electron irregularity.

Fig. 4 DFT calculated molecular vibrational spectra of(C60, Sz =0/2), (C23, Sz =2/2) and (C53, Sz =2/2) comparedwith astronomically observed spectra of carbon rich
nebulae Tc1 and Lin49.
As shown in Fig. 6, possible spin states of C22 are Sz=0/2. 2/2 and 4/2. Most stable state was Sz =2/2, whichenergy was 0.17 eV lower than Sz =4/2 and 1.06 eVlower than Sz =0/2. Spin-distribution was illustrated onright. Similarly, C21 has three pentagons. Stable spinstate was Sz =4/2. In every molecule, there arises
up-spin cloud (by red) at pentagon carbon atom.
Size dependence was checked. Large size molecules
starting from C54 were analyzed as shown in Fig. 7.
Single void induced molecule of C53 show stable spinstate of Sz =2/2. Spin configuration was complex as
illustrated on right column. Two voids induced C52 has
two carbon pentagon rings and show stable spin state ofSz =2/2. Similarly, three voids induced C51 has threepentagons and show stable spin-state of Sz =2/2.

4.2 Infrared spectrum

In Fig. 8, calculated IR were illustrated for moleculesof (C23, Sz =2/2), (C22, Sz =2/2) and (C21, Sz =4/2). It
should be noted that Band-B at 17.4 μm (marked by a
red broken line) was reproduced well by two voids
induced C22, also by three voids induced C21. Other
detailed bands were well reproduced by C22 and C21.
In Fig. 9, calculated spectra of C54 family areillustrated. Both on C53 and C52, we can see the largest
band at 18.9 μm, which just coincide with Band-A.
Unfortunately, we could not find any large intensity at
17.4 μm of Band-B. Number of pentagon rings tohexagons may contribute to the intensity at 17.4 μm.

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At middle wavelength region, Band-D, E, and F werereproduced by C54 family. Also at shorter region, Bandsfrom H to M were reproduced well. While calculatedband at 6.2 μm was not shown by observation. We areafraid of the sensitivity at 6.2 μm, because detection
range of Spitzer/IRS spectra was 6 to 9 μm

Fig. 7 Stable spin-state of larger size graphene C54
family.

Fig. 5 Creation of multi-void induced C24 family.

Fig. 8 Calculated IR of (C23, Sz =2/2), (C22, Sz =2/2) and(C21, Sz =4/2) compared with observation. Band-B was
well reproduced by C22 and C21.

Fig. 6 Stable spin state of graphene C24 family.

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Fig. 9 Calculated spectra of (C53, Sz =2/2), (C52, Sz =2/2)
and (C51, Sz =2/2) compared with observation.

5. Weighting Sum IR
As discussed in a previous section, C60 was difficult toreproduce full bands of astronomical bands as shown on
panel (C) in Fig. 10. A series of multiple void induced
graphene has a capability to reproduce full bands. We
tried a weighting sum spectrum by C23, C22, C53, and C52.
It was demonstrated on panel (D). Observed major
bands of Band-A and B were well reproduced. Also
detailed bands of Band-C, D, E, F, were reproduced well.
Shorter wavelength bands of Band-G, I, K, L and M
were well reproduced again. In panel (E), we add
spectrum of C60 to above weighting sum of graphene. It
looks that major part of (E) was similar with (D). Thereis not any significant difference. Major contribution ofastronomically observed spectrum may come fromgraphene. Fullerene C60 would contribute a part ofthem.

Fig. 10 Astronomical spectrum were compared withcalculated one of C60 in (C), with weighting sum
spectrum of C23, C22, C53 and C52 in (D). Further additionof C60 is illustrated in (E).

6. Laser Induced Carbon Plasma Experiment
As an analogy of astronomical creation of carbon dust,
the laser induced carbon plasma experiment (LICP) wasdone. High power laser irradiates bulk graphite tocreate carbon plasma and finally creates nano-carbon 25).
In third column of Table 1, IR by LICP was noted.
In Fig. 11, we can see rough coincidence of LICP
spectrum with calculated weighting sum IR of C23, C22,
C53 and C52. While as marked on middle, there was little
coincidence with gas-phase experimental two bands of
C60 28).

Fig. 11 Infrared spectrum of the laser induced carbon
plasma experiment was roughly explained by weighting
sum IR of C23, C22, C53 and C52.

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7. Conclusion
A series of multiple void induced graphene molecules
were studied by DFT calculation comparing withastronomical observation and laboratory experiments.
(1) Fullerene C60 gives astronomically observed IR. We
could obtain four bands by calculation. However, there
remain many unidentified astronomical bands.
(2) Single void-defect induced graphene molecule
reproduced well many bands. However, there remain
major astronomical band at 17.4 μm.
(3) A series of multiple-void induced graphene molecules
were studied. Model graphene were C23 (one void
induced one pentagon ring), C22 (two), C21 (three).
Stable spin state was Sz =2/2, Sz =2/2 and Sz =4/2
respectively.
(4) The largest band at 18.9 μm was found in C23.
Second largest band at 17.4 μm was seen both in C22
and C21.
(4) Similarly, large size graphene C53, C52 C51 could also
reproduce astronomical bands as well.
(5) Weighing sum IR by C23, C22, C53 and C52 could
successfully trace observed 12 bands from 6 to 20 μm.
(6) Laboratory experiment of laser induced carbon
plasma suggested rough coincidence of spectrum witha weighing sum IR by C23, C22, C53 and C52.
A series of multiple void induced graphene molecules
would be a major component of astronomical carbon
dust. Fullerene C60 would be a part of them.

Acknowledgement Aigen Li is supported in partby NSF AST-1311804 and NASA NNX14AF68G.
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ApJL: The Astrophysical Journal Letters
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MNRAS: Monthly Notices of the Royal Astronomical Society
PNAS: Proceedings of the National Academy of Sciences
Received June 4, 2021; Revised July 23, 2021; Accepted Sept.
30, 2021

Journal of the Magnetics Society of Japan Vol.45, No.6, 2021

INDEX

Editorial Committee Members・Paper Committee Members
T. Kato and S. Yabukami (Chairperson), K. Koike, K. Kobayashi and Pham NamHai (Secretary)
T. Hasegawa
K. Hioki
S, Inui
K. ItoK. KamataH. Kikuchi
S. Kokado
Y. Kota
T. Kouda
A. Kuwahata
S. Muroga
T. Nagahama
Y. Nakamura
H. Nakayama
T. Narita
T. Nozaki
D. Oyama
T. SatoT. Suetsuna
T. Takura
T. Tanaka
N. Wakiya
T. Yamamoto
K. Yamazaki

Y. Kamihara
K. Masuda
K. Nishijima
K. ThamN. Adachi
T. GotoH. KuraE. Shikoh
M. Toko

M. GotoT. Kojima
M. Sekino
K. Tajima
S. Yoshimura

H. AokiS. Honda
T. MakiK. Suzuki
S. YakataK. Bessho
S. Isogami
M. NaoeI. TagawaS. Yamada

M. DoiM. Iwai
M. OhtakeY. Takamura
A. YaoT. DoiY. Kanai
S. Seino
M. Takezawa
M. Yoshida

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編 集 委 員・論 文 委 員
加 藤 剛 志 （理事） 薮 上
伊藤啓太
乾
成里
小田洋平
佐藤
拓
中山英俊
成田正敬
山本崇史
脇谷尚樹

信 （理事） 小 池 邦 博 （幹事） 小 林 宏 一 郎 （幹事） Pham NamHai（幹事）
小山大介
鎌田清孝
神原陽一
菊池弘昭
桑波田晃弘
神田哲典
末綱倫浩
田倉哲也
田中哲郎
Kim Kong Tham
長浜太郎
西島健一
野崎友大
長谷川崇
日置敬子
増田啓介
室賀
翔

青木英恵
後藤太一
土井正晶
山田晋也

磯上慎二
鈴木和也
都甲
大
吉村
哲

安達信泰
仕幸英治
土井達也
吉田征弘

岩井守生
清野智史
直江正幸

大竹
充
関野正樹
別所和宏

金井
靖
高村陽太
本多周太

藏
裕彰
田河育也
槙
智仁

小嶋隆幸
竹澤昌晃
八尾
惇

古門聡士
仲村泰明
山崎慶太

後藤
穣
田島克文
家形
諭

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