Publication List
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- , Kazuki Komatsu, Kenji Mochizuki, Hayate Ito, Koichi Momma, Shinichi Machida, Takanori Hattori, Kunio Hirata, Yoshiaki Kawano, Saori Maki-Yonekura, Kiyofumi Takaba, Koji Yonekura, Qianli Xue, Misaki Sato, and Hiroyuki Kagi. "New metastable ice phases via supercooled water". arXiv preprint, Submitted.
- Sota Takagi, Naoko Takahashi, Minsu Jang, Huijeng Hwang, Jinhyuk Choi, Hyunseung Lee, Yongmoon Lee, Donghoon Seoung, , Norimasa Ozaki, Pikuz Tatiana, Hirotaka Nakamura, Alexs Amouretti, Toshinori Yabuuchi, Kohei Miyanishi, and Donghoon Kim*. Submitted.
- Mika Yoshioka*, , and Hiroyuki Kagi*. Submitted.
- Masahiro Takano, Hiroyuki Kagi, Yuichiro Mori, , Katsutoshi Aoki, Yoshio Takahashi, Yuta Ijichi, Sho Kakizawa, Noriyoshi Tsujino, Yuji Higo, Asami Sano-Furukawa, and Taku Tsuchiya. Submitted.
- Xuejing He, Hiroyuki Kagi, Kazuki Komatsu, Ronald Miletich, Gerald Giester, Shengxuan Huang, , Sofija Miloš, Herta Effenberger, Satoshi Nakano, and Xiang Wu. Submitted.
- HK et al., in preparation
- HK et al., in preparation
- HK et al., in preparation
- HK et al., in preparation
- HK et al., in preparation
- Co-authored, in preparation
2025
Densification processes of crystalline purine: Negative linear compressibility and pressure-induced phase transition
, Kazuki Komatsu, and Hiroyuki Kagi.
Chemical Physics Letters (2025) 884 142600
DOI: 10.1016/j.cplett.2025.142600
No long-range magnetic order in ε-iron down to 160 mK
Stefan Klotz*, Matteo d'Astuto, Victorien Joyet, , Eddy Lelièvre-Berna, James Maurice, Claude Payre, and Stanislav Savvin.
Applied Physics Letters (2025) 127 211904
DOI: 10.1063/5.0299650
I helped with neutron diffraction experiments led by Stefan at XtremeD, ILL. We managed to measure diffraction patterns at 160 mK and 20 GPa, which is the lowest temperature record at this pressure. We report no evidence for a long-range magnetic ordering in hcp-Fe as suggested by some theoretical studies.
2024
Hydrogen bond symmetrisation in D2O ice observed by neutron diffraction
Kazuki Komatsu*, Takanori Hattori, Stefan Klotz*, Shinichi Machida, Keishiro Yamashita, Hayate Ito, , Tetsuo Irifune, Toru Shinmei, Asami Sano-Furukawa, and Hiroyuki Kagi.
Nature Communications (2024) 15 5100
DOI: 10.1038/s41467-024-48932-8
Project led by Komatsu san. We refined for the first time the hydrogen-atom position in ice VII (X) up to 106 GPa by in-situ powder neutron diffraction using nano-polycrystalline diamond anvil cells. I participated in experiments and discussion.
High-pressure and high-temperature Raman spectroscopic study of zircon as a pressure scale in hydrothermal DACs
Naoko Takahashi*, , and Hiroyuki Kagi.
Journal of Raman Spectroscopy (2024) 55 6 706
DOI: 10.1002/jrs.6663
A collaboration with Naoko, we expanded the p-T region where the zircon Raman pressure scale is applicable. I mainly contributed to synchrotron x-ray diffraction measurements and analysis. Our x-ray diffraction results give a firm support to the previous work by Schmidt et al., with consistency to the standard primary pressure scale of gold.
2023
Slightly Hydrogen-Ordered State of Ice IV Evidenced by In-Situ Neutron Diffraction
, Kazuki Komatsu, Hayate Ito, Shinichi Machida, Takanori Hattori, and Hiroyuki Kagi.
The Journal of Physical Chemistry Letters (2023) 14 10664
DOI: 10.1021/acs.jpclett.3c02563
We reported crystallographic evidence for the hydrogen ordering in ice IV by neutron diffraction. It shows discontinuous behaviour at 120 K and Rietveld analysis at the low-T side suggests it is a very weak hydrogen ordering structural transition.
We studied pressure-induced structural changes in crystalline purine (C5H4N4). The ambient phase persists up to about 0.7 GPa until it transforms into a newly characterised high-pressure phase with a completely different packing structure. We pointed out that the intermolecular hydrogen bonds may be doubled, for which further spectroscopic/theoretical corroboration is desired. If so, we suggest this phase transition is characteristic in purine but not expected in pyrimidine, which has no ability to double the hydrogen bonds.