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A04 Hiroko Tokoro

Hiroko Tokoro

A04 Planning

Affiliation

Faculty of Pure and Applied Sciences, University of Tsukuba

Position

Professor

Contact

tokoro@ims.tsukuba.ac.jp

HP

http://www.ims.tsukuba.ac.jp/~tokoro/index-e.html

Research Project

Creation of Asymmetric Coordination Magnetic Compounds

Abstract

The objectives of this research is to create an asymmetric coordination magnetic compound with a network structure, which has an asymmetric coordination structure and framework. Then, the effects of asymmetric structure on spin are examined via the crystal structure determination and magnetic measurements. Moreover, by considering various physical properties originating from an asymmetric structure, new functionalities are explored. As a target material, we focus on a cyano-bridged complex system containing a cyano group as a ligand, since the cyano group is suitable for intermediating magnetic interactions between metal ions. For example, we plan to focus on a heptacyano bridged metal complex because it has characteristically low-symmetry in the local structure of the metal ion, and a heptacyano metal complex can take various coordination forms. Utilizing these features and selecting the suitable metal ions and ligands for the spin source has possibility to realize new structures, creating a system of asymmetric coordination magnetic compounds with magnetic functionalities.

Research Areas

Solid State Science, Physical Chemistry, Inorganic Material

Keywords

Magnetism, Cooperative effect, Asymmetric structure

2021

[15] Strain wave pathway to semiconductor-to-metal transition revealed by time-resolved X-ray powder diffraction,
C. Mariette; M. Lorenc; H. Cailleau; E. Collet; L. Guérin; A. Volte; E. Trzop; R. Bertoni; X. Dong; B. Lépine; O. Hernandez; E. Janod; L. Cario; V. Ta Phuoc; S. Ohkoshi; H. Tokoro; M. Cammarata; et al.,, Nat. Commun., 12, 1239, 2021
DOI: 10.1038/s41467-021-21316-y.
[14] Advances in magnetic films of epsilon-iron oxide toward next-generation high-density recording media,
Hiroko Tokoro; Asuka Namai; Shin-ichi Ohkoshi, Dalton Trans., 50, 452 – 459, 2021
DOI: 10.1039/d0dt03460f.

2020

[13] “Magnetic pole flip by millimeter wave,
Shin-ichi Ohkoshi; Marie Yoshikiyo; Kenta Imoto; Kosuke Nakagawa; Asuka Namai; Hiroko Tokoro; Yuji Yahagi; Kyohei Takeuchi; Fangda Jia; Seiji Miyashita; Makoto Nakajima; Hongsong Qiu; Kosaku Kato; Takehiro Yamaoka; Masashi Shirata; Kenji Naoi; Koichi Yagishita; Hiroaki Doshita, Adv. Mater., 32, 2004897, 2020
DOI: 10.1002/adma.202004897.
[12] Landau Theory for Non-Symmetry-Breaking Electronic Instability Coupled to Symmetry-Breaking Applied to Prussian Blue Analogue,
G. Azzolina; R. Bertoni; C. Ecolivet; H. Tokoro; S. Ohkoshi; E. Collet, Phys. Rev. B, 102, 134104, 2020
DOI: 10.1103/PhysRevB.102.134104.
[11] Sigmoidally hydrochromic molecular porous crystal with rotatable dendrons,
H. Yamagishi; S. Nakajima; J. Yoo; M. Okazaki; Y. Takeda; S. Minakata; K. Albrecht; K. Yamamoto; I. Badía-Domínguez; M. Moreno Oliva; M. Carmen Ruiz Delgado; Y. Ikemoto; H. Sato; K. Imoto; K. Nakagawa; H. Tokoro; S. Ohkoshi; Y. Yamamoto, Commun. Chem., 3, 118, 2020
DOI: 10.1038/s42004-020-00364-3..
[10] Crystal growth control of rod-shaped ε-Fe2O3 nanocrystals,
H. Tokoro; J. Fukui; K. Watanabe; M. Yoshikiyo; A. Namai; S. Ohkoshi, RSC Adv., 10, 39611 – 39616, 2020
DOI: 10.1039/d0ra07256g.
[9] Synthesis of λ-Ti3O5 nanocrystals using a block copolymer,
Y. Araki; S. Ohkoshi; H. Tokoro, Mater. Today Energy, 18, 100525, 2020
DOI: 10.1016/j.mtener.2020.100525.

2018

[8] Direct Observation of Chemical Conversion from Fe3O4 to ε-Fe2O3 by a Nanosize Wet Process,
H. Tokoro; W. Tarora; A. Namai; M. Yoshikiyo; S. Ohkoshi, Chem. Mater., 30, 2888 – 2894 , 2018
DOI: 10.1021/acs.chemmater.7b03708.
[7] Probing Transient Photoinduced Charge Transfer in Prussian Blue Analogues with Time-Resolved XANES and Optical Spectroscopy,
Serhane Zerdane; Marco Cammarata; Lodovico Balducci; Roman Bertoni; Laure Catala; Sandra Mazerat; Talal Mallah; Martin N. Pedersen; Michael Wulff; Kosuke Nakagawa; Hiroko Tokoro; Shin-ichi Ohkoshi; Eric Collet, Eur. J. Inog. Chem., 3-4, 272 – 277, 2018
DOI: 10.1002/ejic.201700657.
[6] Theoretical prediction of a charge-transfer phase transition,
Hiroko Tokoro; Asuka Namai; Marie Yoshikiyo; Rei Fujiwara; Kouji Chiba; Shin-ichi Ohkoshi, Sci. Rep., 8, 63/1 – 11, 2018
DOI: 10.1038/s41598-017-18213-0.

2017

[5] Cesium Ion Detection by Terahertz Light,
Shin-ichi Ohkoshi; Marie Yoshikiyo; Asuka Namai; Kosuke Nakagawa; Kouji Chiba; Rei Fujiwara; Hiroko Tokoro, Sci. Rep., 7, 8088, 2017
DOI: 10.1038/s41598-017-08551-4.
[4] A novel oxalate-based three-dimensional coordination polymer showing magnetic ordering and high proton conductivity,
Marta Mon; Julia Vallejo; Jorge Pasán; Oscar Fabelo; Cyrille Train; Michel Verdaguer; Shin-ichi Ohkoshi; Hiroko Tokoro; Kosuke Nakagawa; Emilio Pardo, Dalton Trans., 46, 15130 – 15137, 2017
DOI: 10.1039/C7DT03415F.
[3] Large Optical Third-Order Nonlinearities in a Switchable Prussian Blue Analogue,
Amine Ould-Hamouda; Antonio Iazzolino; Hiroko Tokoro; Shin-ichi Ohkoshi; Eric Freysz, Opt. Mater. Express, 7, 2, 444 – 453, 2017
DOI: 10.1364/OME.7.000444.
[2] Electronic Structure and Correlation in β-Ti3O5 and λ-Ti3O5Studied by Hard X-Ray Photoelectron Spectroscopy,
Keisuke Kobayashi; Munetaka Taguchi; Masaaki Kobata; Kenji Tanaka; Hiroko Tokoro; Hiroshi Daimon; Tetsuo Okane; Hiroshi Yamagami; Eiji Ikenaga; Shin-ichi Ohkoshi, Phys. Rev. B, 95, 085133/1 – 085133/7, 2017
DOI: 10.1103/PhysRevB.95.085133.
[1] Dielectric and Optical Constants of λ-Ti3O5 Film Measured by Spectroscopic Ellipsometry,
Fumiyoshi Hakoe; Hiroko Tokoro; Shin-ichi Ohkoshi, Mater. Lett., 188, 8 – 12, 2017
DOI: 10.1016/j.matlet.2016.09.084.