研究者詳細 - 丹羽　健

論文 - 丹羽　健

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Microbeam Hard X-ray Photoemission Study on Platinum-Group Metal Pernitrides

Soda, K; Mizui, T; Komabuchi, M; Kato, M; Terabe, T; Suzuki, K; Niwa, K; Shirako, Y; Hasegawa, M; Akaogi, M; Kojitani, H; Ikenaga, E

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 86 巻 ( 6 ) 頁： 64804 - 64804 2017年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of the Physical Society of Japan

Using microbeam hard X-ray photoelectron spectroscopy, we clarified the valence-band electronic structures and chemical states of platinum-group metal (Ru, Ir, and Pt) pernitrides, which have been synthesized in supercritical nitrogen fluid under extremely high pressures and temperatures. Their nitrogen contents relative to the platinum-group metal are estimated to be 2 from the photoemission intensity, which is consistent with the studies reported to date. The observed valence-band structures agree quite well with theoretically predicted structures for the pyrite-type PtN2, arsenopyrite-type IrN2, and marcasite-type RuN2. The origin of their extremely large bulk moduli is discussed based on the current results of the valence-band structures and core-level chemical shifts.

DOI： 10.7566/JPSJ.86.064804

Web of Science

Scopus

CiNii Research

Highly Coordinated Iron and Cobalt Nitrides Synthesized at High Pressures and High Temperatures

Niwa, K; Terabe, T; Kato, D; Takayama, S; Kato, M; Soda, K; Hasegawa, M

INORGANIC CHEMISTRY 56 巻 ( 11 ) 頁： 6410 - 6418 2017年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Inorganic Chemistry

Highly coordinated iron and cobalt nitrides were successfully synthesized via direct chemical reaction between a transition metal and molecular nitrogen at pressures above approximately 30 GPa using a laser-heated diamond anvil cell. The synthesized novel transition metal nitrides were found to crystallize into the NiAs-type or marcasite-type structure. NiAs-type FeN could be quenched at ambient pressure, although it was gradually converted to the ZnS-type structure after the pressure was released. On the other hand, CoN was recovered with ZnS-type structure through a phase transition from NiAs-type structure at approximately a few gigapascals during decompression. Marcasite-type CoN2 was also synthesized at pressures above approximately 30 GPa. High-pressure in situ X-ray diffraction measurement showed that the zero-pressure bulk modulus of marcasite-type CoN2 is 216(18) GPa, which is comparable to that of RhN2. This indicates that the interatomic distance of the N-N dimer in marcasite-type CoN2 is short because of weak orbital interaction between cobalt and nitrogen atoms, as in RhN2. Surprisingly, a first-principles electronic band calculation suggests that the NiAs-type FeN and CoN and marcasite-type CoN2 exhibit metallic characteristics with magnetic moments of 3.4, 0.6, and 1.2 μB, respectively. The ferromagnetic NiAs-type structure originates from the anisotropic arrangement of transition atoms stacked along the c axis.

DOI： 10.1021/acs.inorgchem.7b00516

Synthesis, crystal structure and phase transition of a Xe-N2 compound at high pressure: experimental indication of orbital interaction between xenon and nitrogen

Niwa, K; Matsuzaki, F; Hasegawa, M

PHYSICAL CHEMISTRY CHEMICAL PHYSICS 19 巻 ( 1 ) 頁： 59 - 63 2017年1月

High-Pressure Synthesis and Magnetic Behavior of A-Site Columnar-Ordered Double Perovskites, LnMn(Ga0.5Ti0.5)2O6 (Ln = Sm, Gd)

Shimura, G; Niwa, K; Shirako, Y; Hasegawa, M

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY 2017 巻 ( 4 ) 頁： 835 - 839 2017年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：European Journal of Inorganic Chemistry

A-site columnar-ordered double perovskites, LnMn(Ga0.5Ti0.5)2O6(Ln = Sm, Gd), were successfully synthesized under high pressure and high temperature (6 GPa, 1375 K). From the synchrotron powder X-ray diffraction patterns, all of the diffraction peaks can be indexed by the P42/nmc space group with lattice parameters a, c ≈ 2ap(ap: primitive cubic perovskite lattice) and no ordering of the B-site cations. Rietveld analysis of the synchrotron powder X-ray diffraction patterns and Curie–Weiss fitting of their magnetizations reveal that the ionic formulae of these perovskites are Ln3+Mn2+(Ga3+0.5Ti4+0.5)2O2–6. SmMn(Ga0.5Ti0.5)2O6shows canted-antiferromagnetic behavior, whereas GdMn(Ga0.5Ti0.5)2O6exhibits two different magnetic states at low temperature depending on the applied magnetic field and shows an unusual magnetization curve. These magnetic behaviors originate by decreasing the antiferromagnetic interaction by substituting Ga3+(d10) for Ti4+(d0) and by decreasing the ferromagnetic interaction between columnar-ordered Ln3+and Mn2+.

DOI： 10.1002/ejic.201601392

Web of Science

Scopus

CiNii Research

Microbeam hard X-ray photoelectron and ion-beam analyses of Nb hydrides formed in supercritical water

Kazuo Soda, Shinya Sugiura, Kanta Yamaguchi, Masahiko Kato, Ken Niwa, Masashi Hasegawa, Kohtaku Suzuki, Ryoya Ishigami, Eiji Ikenaga

International Symposium on Atomic Level Characterizations for New Materials and Devices ‘17 Proceedings 2017年

Multicomponent A-site ordered perovskite BiMn3(Fe0.25Ti0.75)4O12: High-pressure synthesis, crystal chemistry and magnetic behavior 査読有り

G. Shimura, K. Niwa, Y. Shirako, S. Muto, K. Kusaba, M. Hasegawa

Solid State Communications 234-235 巻頁： 40-44 2016年

High pressure stability and ambient metastability of marcasite-type rhodium pernitride 査読有り

K. Niwa, T. Terabe, K. Suzuki, Y. Shirako, M. Hasegawa

Journal of Applied Physics 119 巻頁： 065901 2016年

Molecular routes syntheses of graphite-like C-N compounds with various N/C ratios in high pressure and temperature 査読有り

T. HORIBE, K. KUSABA, K. NIWA, M. HASEGAWA, K. YASUDA, R. ISHIGAMI

Journal of the Ceramic Society of Japan 124 巻 ( 10 ) 頁： 1013-1016 2016年

High-pressure synthesis and relationship between A-site ordering and local structure of multicomponent perovskites(Ln0.25Mn0.75) (Al0.25Ti0. 75)O3, Ln=La, Pr, Nd, Sm, Gd, Tb, Dy, Y 査読有り

G. Shimura, Y. Shirako, K. Niwa, M. Hasegawa

Journal of Solid State Chemistry 242 巻頁： 55-62 2016年

Angle-resolved hard x-ray photoemission study of Nb hydride formation in high-pressure supercritical water 査読有り

Kazuo Soda, Hiroki Kondo, Kanta Yamaguchi, Masahiko Kato, Tatsuhito Shirak, Ken Niwa, Keiji Kusaba, Masashi Hasegawa, Kozina Xeniya, Eiji Ikenaga

Journal of Alloys and Compounds 643 巻頁： 195-200 2015年

Growth of rectangular hollow tube crystals with rutile-type structure in supercritical fluids 査読有り

K. Niwa, H. Ikegaya, T. Taguchi, S. Muto, T. Tokunaga and M. Hasegawa

Journal of Physics: Conference Series (JPCS) 500 巻頁： 022007 2014年

High pressure synthesis of marcasite-type rhodium pernitride 査読有り国際共著

K. Niwa, D. Dzivenko, K. Suzuki, R. Riedel, I. Troyan, M. Eremets and M. Hasegawa

Inorganic Chemistry 53 巻頁： 697-699 2014年

レーザー加熱式ダイアモンドアンビルセルを用いた新物質合成招待有り査読有り

丹羽健，長谷川正

高圧力の科学と技術 24 巻頁： 178-187 2014年

Discovery of the last remaining binary platinum group pernitride RuN2 査読有り

K. Niwa, K. Suzuki, S. Muto, K. Tatsumi, K. Soda, T. Kikegawa and M. Hasegawa

Chemistry-A European Journal 20 巻 ( 43 ) 頁： 13885 - 13888 2014年

Argon Solubility in SiO2 Melt under High Pressures : A New Experimental Result using Laser-Heated Diamond-Anvil Cell 査読有り

K. Niwa, C. Miyakawa, J. Matsuda, T. Yagi

Earth and Planetary Science Letters 363 巻頁： 1-8 2013年

Characterization of Nb Hydrides Synthesized in High-Pressure Supercritical Water by Micro-beam Hard X-ray Photoelectron Spectroscopy 査読有り

K. Soda, H. Kondo, M. Kato, T. Shiraki, K. Niwa, K. Kusaba, M. Hasegawa, E. Ikenaga

Journal of Electron Spectroscopy and Related Phenomena 186 巻頁： 54-57 2013年

Pressure-induced noble gas insertion into zeolite LTA and its incompressible behaviors at high pressure 査読有り

K. Niwa, T. Tanaka, M. Hasegawa, T. Okada, T. Yagi, K. Kikegawa

MICROPOROUS AND MESOPOROUS MATERIALS 182 巻頁： 191-197 2013年

Effects of Sn2+ Ion Size on Sn Doped SrTiO3 査読有り

S. Suzuki, A. Honda, K. Suzuki, S. Higai, A. Ando, K. Niwa, M. Hasegawa

Japanese Journal of Applied Physics 52 巻頁： 09KC04 2013年

In-situ observation of shear stress-induced perovskite to post-perovskite phase transition in CaIrO3 and the development of its deformation texture in a diamond-anvil cell up to 30 GPa 査読有り

K. Niwa, N. Miyajima, Y. Seto, K. Ohgushi, H. Gotou, T. Yagi

Physics of the Earth and Planetary Interiors 194-195 巻頁： 10–17 2012年

High pressure induced water penetration into 3-isopropylmalate dehydrogenase 査読有り

T. Nagae, T. Kawamura, L. Chavas, K. Niwa, M. Hasegawa, C. Kato, N. Watanabe

Acta Crystallographica D 68 巻頁： 300–309 2012年

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