The Mystery behind Dynamic Charge Disproportionation in BaBiO3

被引：17

作者：

Sarkar, Sumit ^{[1
]}

Raghunathan, Rajamani ^{[1
]}

Chowdhury, Sourav ^{[1
]}

Choudhary, Ram Janay ^{[1
]}

Phase, Deodatta Moreshwar ^{[1
]}

机构：

[1] UGC DAE Consortium Sci Res, Indore 452001, India

来源：

NANO LETTERS | 2021年 / 21卷 / 19期

关键词：

charge disproportionation; X-ray spectroscopy; density functional theory; thin films; molecular orbital theory; METAL-SEMICONDUCTOR TRANSITION; INITIO MOLECULAR-DYNAMICS; ELECTRONIC-STRUCTURE; INVERSE-PHOTOEMISSION; THIN-FILMS; ENERGY; SUPERCONDUCTIVITY; BAPB1-XBIXO3; DENSITY; STATES;

D O I：

10.1021/acs.nanolett.1c03103

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

BaBiO3(BBO) is known to be a valence-skipping perovskite, which avoids the metallic state through charge disproportionation (CD), the mechanism of which is still unresolved. A novel mechanism for CD is presented here in the covalent limit using a molecular orbital (MO) picture under two scenarios: (case i) Bi 6sp-O 2p and (case ii) Bi 6p-O 2p hybridizations that favor 5+ and 3+ states, respectively. The proposed model is further validated by using a combinatorial approach of X-ray spectroscopic experiments and first-principle calculations. The bulk X-ray photoemission spectrum reveals that, at room temperature, the CD is dynamic in nature, whereas, at 200 K, it approaches a quasi-static limit. Under compressive strain, the octahedral breathing mode is damped and drives the system to a quasi-static limit even at room temperature, giving rise to asymmetric CD.

引用

页码：8433 / 8438

页数：6

共 45 条

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