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中西 匠*; 堀 優太*; 重田 育照*; 佐藤 寛泰*; 鬼柳 亮嗣; 宗像 孝司*; 大原 高志; 岡澤 厚*; 島田 林太郎*; 坂本 章*; et al.
Journal of the American Chemical Society, 145(35), p.19177 - 19181, 2023/08
被引用回数：0 パーセンタイル：0(Chemistry, Multidisciplinary)Multiple proton transfer (PT) controllable by external stimuli plays a crucial role in fundamental chemistry, biological activity, and material science. However, in crystalline systems, controlling multiple PT, which results in a distinct protonation state, remains challenging. In this study, we developed a novel tridentate ligand and iron(II) complex with a short hydrogen bond (HB) that exhibits a PT-coupled spin transition (PCST). Single-crystal X-ray and neutron diffraction measurements revealed that the positions of the two protons in the complex can be controlled by temperature and photoirradiation based on the thermal- and photoinduced PCST. The obtained results suggest that designing molecules that form short HBs is a promising approach for developing multiple PT systems in crystals.
Sn
( = Rh and Ir)下田 愛海*; 岩佐 和晃*; 桑原 慶太郎*; 佐賀山 基*; 中尾 裕則*; 石角 元志*; 大原 高志; 中尾 朗子*; 星川 晃範*; 石垣 徹*
JPS Conference Proceedings (Internet), 38, p.011091_1 - 011091_6, 2023/05
Synchrotron X-ray diffraction study revealed that NdSn ( = Rh and Ir) undergo structural phase transitions characterized by the wave vector 
=(1/2,1/2,0). Neutron diffraction study revealed antiferromagnetic ordering below 
= 1.65 and 1.42 K for NdRhSn and NdIrSn, respectively, which is similar to that previously reported for NdCoSn. These compounds show a magnetic susceptibility saturation behavior below approximately 3 K. The results indicate emergence of anomalous electronic correlation in NdSn ( = Co, Rh, and Ir) above .
中西 匠*; 堀 優太*; 重田 育照*; 佐藤 寛泰*; Wu, S.-Q.*; 鬼柳 亮嗣; 宗像 孝司*; 大原 高志; 佐藤 治*
Physical Chemistry Chemical Physics, 25(17), p.12394 - 12400, 2023/05
被引用回数：1 パーセンタイル：56.86(Chemistry, Physical)The application of single-crystal neutron diffraction (SCND) to observe proton-transfer phenomena in crystalline compounds exhibiting unusual protonation states or proton dynamics has garnered significant research interest in recent years. However, proton tautomerism, which results in different protonation states before and after proton transfer, has never been observed using the SCND technique. Thus, to observe the proton tautomerism phenomenon by SCND measurements, we developed an iron(II) complex that forms a large crystal and exhibits a proton-transfer-coupled spin transition (PCST). The presence of the two types of proton tautomers was determined by conventional analysis of the proton position by X-ray crystallography, infrared spectroscopy, and density functional theory calculations. Finally, our results confirmed that proton tautomerism was successfully observed for the first time using variable-temperature SCND measurements.
大原 高志
日本結晶学会誌, 64(2), p.132 - 139, 2022/05
中性子を用いる単結晶中性子回折法は原子核の位置を直接観察できることに加えて水素原子に対する感度が高いことから、結晶中の水素原子位置を高精度で確実に観察できる強力な手法となる。日本国内では1990年代末からJRR-3研究用原子炉を中心に単結晶中性子回折計の開発が進み、金属錯体など格子体積の比較的大きい分子性結晶における水素原子の観察が現実的になるとともに、より大強度の中性子源であるJ-PARCの建設が始まった。そのなかで筆者は単結晶中性子回折計の開発と並行して、単結晶中性子構造解析による分子性結晶中の水素原子の確実な観察を基にした研究を展開してきた。本稿では、これらの水素原子が鍵となる研究について概説する。
山下 恵史朗*; 小松 一生*; 大原 高志; 宗像 孝司*; 入舩 徹男*; 新名 亨*; 杉山 和正*; 川又 透*; 鍵 裕之*
High Pressure Research, 42(1), p.121 - 135, 2022/03
被引用回数：3 パーセンタイル：58.88(Physics, Multidisciplinary)We improved diamond anvil cells with a tubular frame made of Zr-based bulk metallic glass and nano-polycrystalline diamond anvils for single-crystal neutron diffraction. The thicker tubular frame was confirmed through experimentation as stably generating 4.5 GPa. Its feasibility for neutron diffraction was assessed at the Laue-TOF diffractometer at the BL18 (SENJU) beamline in the MLF J-PARC using time-resolved two-dimensional detectors covering wide solid angles. In addition to ambient-pressure measurements of NHCl, diffraction patterns of a high-pressure phase of ice were also collected in-situ. The obtained intensities are of refinable quality sufficient for structure analysis.
GeP
S
矢島 健*; 日沼 洋陽*; 堀 智*; 岩崎 類*; 菅野 了次*; 大原 高志; 中尾 朗子*; 宗像 孝司*; 廣井 善二*
Journal of Materials Chemistry A, 9(18), p.11278 - 11284, 2021/05
被引用回数：19 パーセンタイル：80.41(Chemistry, Physical)Herein, we studied the crystalline compound LiGePS with the largest Li-ion conductivity thus far via a novel route based on a combination of single-crystal neutron diffraction experiments at low temperature and first-principles calculations, and found that a correlated migration of the densely packed Li ions governs the overall Li-ion conduction. The correlated migration mechanism provides us with guidelines on how to design efficient superionic conductors for more efficient batteries.
FeO
Cl with tunable direction in three dimensions阿部 伸行*; 塩澤 俊介*; 松浦 慧介*; 佐賀山 基*; 中尾 朗子*; 大原 高志; 徳永 祐介*; 有馬 孝尚*
Physical Review B, 101(18), p.180407_1 - 180407_5, 2020/05
被引用回数：2 パーセンタイル：12.9(Materials Science, Multidisciplinary)The correlation between magnetism and electric polarization in a chiral insulating magnet BaFeOCl has been investigated. The temperature dependence of magnetic susceptibility shows an anomaly at 564 K, suggesting the onset of antiferromagnetic order of Fe
moments. Electric polarization appears in a magnetic field below TN due to the spin-direction-dependent metal-ligand hybridization. The direction of the electric polarization can be controlled in three-dimensional space by changing the direction of an external magnetic field. This compound also shows an antiferromagnetic-to-weak-ferromagnetic transition accompanied by a structural phase transition at 140 K.
IrSn (
: La and Ce) investigated using neutron and X-ray diffraction中里 晟也*; 岩佐 和晃*; 橋本 大輔*; 塩澤 真未*; 桑原 慶太郎*; 中尾 裕則*; 佐賀山 基*; 石角 元志*; 大原 高志; 中尾 朗子*; et al.
JPS Conference Proceedings (Internet), 30, p.011128_1 - 011128_6, 2020/03
Successive phase transitions of IrSn (: La and Ce) were studied using neutron and X-ray diffraction techniques. A semimetal CeIrSn undergoes three phase transitions: an antiferromagnetic ordering characterized by a propagation vector 
= (1/2, 1/2, 2/5) below 0.6 K, a structural transformation with 
= (1/4, 1/4, 1/4) at 2.0 K, and another structural transformation with 
= (1/2, 1/2, 0) above room temperature. LaIrSn was confirmed to be a superconductor below 2.5 K under the = (1/2, 1/2, 0) structure that also appears above room temperature.
CoFe
O
駒淵 舞*; 漆原 大典*; 浅香 透*; 福田 功一郎*; 大原 高志; 宗像 孝司*; 石川 喜久*
Journal of the Physical Society of Japan, 89(3), p.034601_1 - 034601_5, 2020/03
被引用回数：2 パーセンタイル：22.16(Physics, Multidisciplinary)The crystal structure of an X-type hexaferrite SrCoFeO was investigated by the X-ray and neutron diffraction methods for a single crystal. SrCoFeO has the crystal structure described as a space group 
(
) and its lattice constants are 
= 5.9165(2) 
; and 
= 84.1395(33) ; at 843 K. Co ions are almost localized in the octahedral site (
) in the middle of S
S blocks. In addition, the adjacent octahedral and tetrahedral sites to site contain the significant number of Co
.
中根 僚宏*; 米山 翔太*; 兒玉 健*; 菊地 耕一*; 中尾 朗子*; 大原 高志; 東中 隆二*; 松田 達磨*; 青木 勇二*; 藤田 渉*
Dalton Transactions (Internet), 48(1), p.333 - 338, 2019/01
被引用回数：2 パーセンタイル：11.34(Chemistry, Inorganic & Nuclear)The two-dimensional quadratic lattice magnet, bis(glycolato)cobalt(II) ([Co(HOCHCO)]), showed anti-ferromagnetic ordering at 15.0 K and an abrupt increase in magnetisation at H = 22 600 Oe and 2 K, thereby acting as a metamagnet. Neutron diffraction studies suggested that the magnetic moment vectors of the Co(II) ions had an amplitude of 3.59 mB and were not aligned in a fully antiparallel fashion to those of their neighbours, which caused canting between the magnetic moment vectors in the sheet. The canting angle was determined to be 7.1deg. Canting induced net magnetisation in the sheet, but this magnetisation was cancelled between sheets. The magnetisations in the sheets were oriented parallel to the magnetic field at the critical magnetic field.
VAl Heusler alloy thin films; Appearance of antiferromagnetism and exchange bias in a layered structure with Fe土屋 朋生*; 小林 亮太*; 窪田 崇秀*; 斉藤 耕太郎*; 小野 寛太*; 大原 高志; 中尾 朗子*; 高梨 弘毅*
Journal of Physics D; Applied Physics, 51(6), p.065001_1 - 065001_7, 2018/02
被引用回数：10 パーセンタイル：45.99(Physics, Applied)MnVAl Heusler alloy films were epitaxially grown on MgO(100) single-crystal substrates by ultra-high-vacuum magnetron sputtering. A2- and L21-type MnVAl order was controlled by the deposition temperature. A2-type MnVAl films showed no spontaneous magnetization, while L21-type MnVAl films showed ferrimagnetic behaviour with a maximum saturation magnetization of 220 emu/cm
at room temperature (RT). An antiferromagnetic reflection was observed with neutron diffraction at RT for an A2-type MnVAl film deposited at 400
C. A bilayer sample of the antiferromagnetic A2-type MnVAl and Fe showed an exchange bias of 120 Oe at 10 K.
増田 敏幸*; Arase, Junko*; 稲垣 佑亮*; 川幡 正俊*; 山口 健太郎*; 大原 高志; 中尾 朗子*; 門馬 洋行*; Kwon, E.*; 瀬高 渉*
Crystal Growth & Design, 16(8), p.4392 - 4401, 2016/08
被引用回数：27 パーセンタイル：87.56(Chemistry, Multidisciplinary)Three-dimensional arrays of dipolar rotors were constructed as single crystals of molecular gyrotops, which are macrocage molecules with a bridged dipolar rotor. In this study, we synthesized novel molecular gyrotops with a five-membered heteroring, i.e., furan-diyl, thiophenediyl, and selenophene-diyl, and investigated the temperature-dependent orientation and rotation of the dipolar rotors inside the crystal.
犬飼 宗弘*; 堀毛 悟史*; 板倉 智也*; 篠崎 良太*; 荻原 直希*; 梅山 大樹*; Nagarker, S.*; 西山 裕介*; Malon, M.*; 林 灯*; et al.
Journal of the American Chemical Society, 138(27), p.8505 - 8511, 2016/07
被引用回数：135 パーセンタイル：95.46(Chemistry, Multidisciplinary)We describe encapsulation of mobile proton carriers into defect sites in non-porous coordination polymers. The proton carriers are encapasulated with high mobility and provide high proton conductivity at 150C under anhydrous condition. The high proton conductivity and non-porous nature allow power generation by fuel cell in which CPs are used as electrolyte. To observe defects and mobile proton carriers, we carried out solid-state NMR, XAFS, XRD, and ICP-AES/EA. On the basis of these analyses, we elucidated that the defect sites provide space for mobile uncoordinated HPO, HPO
, and HO. These mobile carriers play a key role to expand proton hopping path and promote the mobility of all protons in coordination frameworks, leading to high proton conductivity and fuel cell power generation.
大原 高志; 鬼柳 亮嗣; 及川 健一; 金子 耕士; 川崎 卓郎; 田村 格良; 中尾 朗子*; 花島 隆泰*; 宗像 孝司*; 茂吉 武人*; et al.
Journal of Applied Crystallography, 49(1), p.120 - 127, 2016/02
被引用回数：51 パーセンタイル：95.86(Chemistry, Multidisciplinary)SENJU, a time-of-flight Laue-type single-crystal neutron diffractometer, was developed at the Materials and Life Science Experimental Facility (MLF) of the Japan Accelerator Research Complex (J-PARC). Molecular structure analysis of a sub-millimeter taurine crystal and magnetic structure analysis of a MnF crystal were performed to evaluate its performance.
阿久津 和宏*; 大原 高志
ぶんせき, 2014(11), p.617 - 621, 2014/11
J-PARCのMLFでは現在18本の中性子ビームラインに実験装置が設置され、世界最高強度のパルス中性子ビームを用いた学術研究や産業利用が行われている。本稿では、J-PARCおよびMLFの中性子実験施設の概要、中性子の特徴を紹介するとともに、中性子実験装置の一つである単結晶回折計「千手」の特徴に触れながら中性子結晶構造解析について説明する。
大原 高志
no journal, ,
J-PARC/MLFでは現在2台の単結晶回折計が稼働している。これらの回折計ではパルス中性子の特徴を利用したtime-of-flight(TOF) Laue法によって広い逆空間を一度にスキャンできるため、J-PARCの大強度中性子と相まって従来に比べて小さい0.5mm角程度の単結晶試料を用いた測定が現実的なビームタイムで可能となった。加えて、SENJUでは極低温(
4K)や磁場(7T)環境下での測定が可能であり、高温や高圧、電場といった様々な試料環境の整備も進めている。これにより、これまで結晶サイズの問題から測定を諦めざるを得なかった様々な機能性有機・有機金属結晶の単結晶中性子構造解析を、その機能が発現する環境下で実現できると期待される。本講演ではJ-PARCの単結晶中性子回折計を活用した結晶化学の最新状況を紹介する。
大原 高志; 鬼柳 亮嗣; 中尾 朗子*; 花島 隆泰*; 宗像 孝司*; 茂吉 武人*; 黒田 哲也*; 金子 耕士; 田村 格良; 及川 健一; et al.
no journal, ,
SENJU, a TOF-Laue single crystal neutron diffractometer at the BL18 of MLF/J-PARC, was designed for precise crystal and magnetic structure analyses under multiple extreme environments such as low-temperature, high-pressure and high-magnetic field, and also capable of taking diffraction measurements of small single crystals. The most popular sample environment device on SENJU is the 4 K cryostat with a fixed-chi type 2-axes goniometer. We adopted piezo-rotators to rotate the sample crystal under vacuumed and cryo conditions. The 2-axes goniometer works stably even at 4 K and the time for cooling was 4.5 hours. A longitudinal magnet was recently installed on SENJU. The lowest temperature was 1.42 K and the maximum magnetic field was 6.85 T. A test diffraction measurement of a CeCoGe3 single crystal under 1.5 K and 0.5 T showed that Bragg reflections from the sample was clearly observed and the Bragg peaks of the sample crystal were much higher than the peaks from the magnet itself.
大原 高志
no journal, ,
単結晶中性子構造解析は水素原子をはじめとした軽原子を観察する強力な手段であり、結晶化学の分野においても金属ヒドリド錯体中の水素原子や特殊な水素結合系の水素原子など、位置を予想できない水素原子を観察するほぼ唯一の手段として用いられてきた。一方、単結晶中性子構造解析では線源の輝度がX線に比べて小さいために数ミリ角という巨大な単結晶が必要であったが、MLFでは0.5mm角程度という従来に比べて小さい単結晶試料を用いた測定が現実的なビームタイムで可能となり、測定の対象となり得る試料は大きく拡大した。本講演では分子性結晶における単結晶中性子構造解析の実例やTOF Laue法を用いた単結晶中性子回折測定の原理について解説するとともに、MLFの単結晶回折計での構造解析の実際についても紹介する。
大原 高志; 花島 隆泰*; 宗像 孝司*; 茂吉 武人*; 鬼柳 亮嗣; 中尾 朗子*; 黒田 哲也*
no journal, ,
Photo-induced crystalline-state properties such as light-emission and magnetism of organic molecular crystals have been actively investigated because they can derive new photo-functional organic materials. In this research, we developed a new closed-cycle cryostat with 2-axes goniometer in which visible white light can be induced to carry out an in-situ single crystal neutron structure analysis of a photo-induced species in a single crystal on SENJU, a TOF-Laue single crystal diffractometer at MLF/J-PARC.
大原 高志; 鬼柳 亮嗣; 中尾 朗子*; 宗像 孝司*; 茂吉 武人*; 森山 健太郎*; 花島 隆泰*; 黒田 哲也*
no journal, ,
Single-crystal neutron diffraction is one of the most fundamental and powerful techniques to determine the arrangement of light elements and magnetic moments in crystalline materials with high accuracy and reliability. We constructed a TOF-Laue single crystal neutron diffractometer, SENJU, at the BL18 of MLF/J-PARC, for precise crystal and magnetic structure analyses. In this presentation, we will show some recent scientific achievements and instrument advances of SENJU.
