Enhanced Negative Thermal Expansion Induced by Simultaneous Charge Transfer and Polar-Nonpolar Transitions

Takumi Nishikubo; Yuki Sakai; Kengo Oka; Tetsu Watanuki; Akihiko Machida; Masaichiro Mizumaki; Koki Maebayashi; Takashi Imai; Takahiro Ogata; Keisuke Yokoyama; Yoichi Okimoto; Shin-Ya Koshihara; Hajime Hojo; Takashi Mizokawa; Masaki Azuma

doi:10.1021/jacs.9b10336

Enhanced Negative Thermal Expansion Induced by Simultaneous Charge Transfer and Polar-Nonpolar Transitions

J Am Chem Soc. 2019 Dec 11;141(49):19397-19403. doi: 10.1021/jacs.9b10336. Epub 2019 Dec 2.

Authors

Takumi Nishikubo¹, Yuki Sakai^{1

2}, Kengo Oka³, Tetsu Watanuki⁴, Akihiko Machida⁴, Masaichiro Mizumaki⁵, Koki Maebayashi¹, Takashi Imai¹, Takahiro Ogata¹, Keisuke Yokoyama⁶, Yoichi Okimoto⁶, Shin-Ya Koshihara⁶, Hajime Hojo⁷, Takashi Mizokawa⁸, Masaki Azuma^{1

2}

Affiliations

¹ Laboratory for Materials and Structures , Tokyo Institute of Technology , 4259 Nagatsuta, Midori-ku , Yokohama , Kanagawa 226-8503 , Japan.
² Kanagawa Institute of Industrial Science and Technology , 705-1 Shimoimaizumi , Ebina , Kanagawa 243-0435 , Japan.
³ Department of Applied Chemistry, Faculty of Science and Engineering , Kindai University , 3-4-1 Kowakae , Higashiosaka , Osaka 577-8502 , Japan.
⁴ Synchrotron Radiation Research Center , National Institutes for Quantum and Radiological Science and Technology , 1-1-1 Kouto , Sayo , Hyogo 679-5148 , Japan.
⁵ Japan Synchrotron Radiation Research Institute , SPring-8, 1-1-1 Kouto , Sayo , Hyogo 679-5198 , Japan.
⁶ Department of Chemistry , Tokyo Institute of Technology , 2-12-1 Ookayama , Meguro , Tokyo 152-8551 , Japan.
⁷ Department of Advanced Materials Science and Engineering, Faculty of Engineering Sciences , Kyushu University , 6-1 Kasuga-koen , Kasuga , Fukuoka 816-8580 , Japan.
⁸ Department of Applied Physics, School of Advanced Science and Engineering , Waseda University , 3-4-1 Okubo , Shinjuku , Tokyo 169-8555 , Japan.

PMID: 31738059
DOI: 10.1021/jacs.9b10336

Abstract

Negative thermal expansion (NTE) induced by simultaneous mechanisms, that is, charge transfer and polar-nonpolar transitions, was observed for the first time in BiNi_1-xFe_xO₃ (0.25 ≤ x ≤ 0.5). The low-temperature phase was found to have a polar structure (space group of R3c) with a Bi³⁺_0.5(1+x)Bi⁵⁺_0.5(1-x)Ni²⁺_1-xFe³⁺_xO₃ charge distribution and short-range ordering of Bi³⁺ and Bi⁵⁺. The volume reduction upon heating that was induced by charge transfer between Bi⁵⁺ and Ni²⁺ decreased with increasing x because of the reduction in the amount of Ni²⁺. Simultaneous polar-nonpolar transition also contributed to NTE, and a composition-independent enhanced volume reduction of ∼2% was observed.