高压PdF₂型氧化物MO₂（M = Ru、Rh、Os、Ir、Pt）的合成、晶体结构及电子性质

Synthesis, crystal structure, and electronic properties of high-pressure PdF2-type oxides MO2 (M = Ru, Rh, Os, Ir, Pt).

作者信息

Shirako Yuichi, Wang Xia, Tsujimoto Yoshihiro, Tanaka Kie, Guo Yanfeng, Matsushita Yoshitaka, Nemoto Yoshihiro, Katsuya Yoshio, Shi Youguo, Mori Daisuke, Kojitani Hiroshi, Yamaura Kazunari, Inaguma Yoshiyuki, Akaogi Masaki

机构信息

Department of Chemistry, Gakushuin University , 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan.

出版信息

Inorg Chem. 2014 Nov 3;53(21):11616-25. doi: 10.1021/ic501770g. Epub 2014 Oct 22.

DOI:10.1021/ic501770g

PMID:25337807

Abstract

The polycrystalline MO2's (HP-PdF2-type MO2, M = Rh, Os, Pt) with high-pressure PdF2 compounds were successfully synthesized under high-pressure conditions for the first time, to the best of our knowledge. The crystal structures and electromagnetic properties were studied. Previously unreported electronic properties of the polycrystalline HP-PdF2-type RuO2 and IrO2 were also studied. The refined structures clearly indicated that all compounds crystallized into the HP-PdF2-type structure, M(4+)O(2-)2, rather than the pyrite-type structure, M(n+)(O2)(n-) (n < 4). The MO2 compounds (M = Ru, Rh, Os, Ir) exhibited metallic conduction, while PtO2 was highly insulating, probably because of the fully occupied t2g band. Neither superconductivity nor a magnetic transition was detected down to a temperature of 2 K, unlike the case of 3d transition metal chalcogenide pyrites.

摘要

据我们所知，首次在高压条件下成功合成了具有高压PdF₂化合物的多晶MO₂（HP-PdF₂型MO₂，M = Rh、Os、Pt）。对其晶体结构和电磁性质进行了研究。还研究了多晶HP-PdF₂型RuO₂和IrO₂此前未报道的电子性质。精细结构清楚地表明，所有化合物均结晶为HP-PdF₂型结构M(4+)O(2-)₂，而非黄铁矿型结构M(n+)(O₂)(n-)（n < 4）。MO₂化合物（M = Ru、Rh、Os、Ir）表现出金属导电性，而PtO₂则高度绝缘，这可能是由于t₂g能带被完全占据。与3d过渡金属硫属化物黄铁矿的情况不同，在2 K的温度下未检测到超导性或磁转变。