title: Pressure-induced magnetic moment collapse and insulator-to-semimetal transition in BiCoO(3).
abstract: The structural stability, magnetic properties and electronic structure of tetragonal BiCoO(3) under pressure have been studied by first-principles density functional calculations. The calculated results reveal that no tetragonal-to-cubic and ferroelectric-to-paraelectric phase transitions occur up to 30 GPa with a volume compression of about 25%. An electronic spin crossover transition of the Co(3+) ion from the high-spin to nonmagnetic low-spin configuration (magnetic moment collapse) occurs at 4 GPa by about 4.87% volume compression, which is concomitant with a first-order isosymmetric transition and an insulator-to-semimetal transition. The metallization in BiCoO(3) is driven by the spin-state transition at high pressure. Coexistence of the structural, spin-state and insulator-to-semimetal transitions implies that there is a strong coupling among the lattice, spin and charge degrees of freedom in BiCoO(3).
authors.affiliation: Department of Materials Science, College of Materials Science and Engineering, Jilin University, Changchun 130012, People's Republic of China.
authors.forename: Xing
authors.initials: X
authors.lastname: Ming
authors.forename: Xing
authors.initials: X
authors.lastname: Meng
authors.forename: Fang
authors.initials: F
authors.lastname: Hu
authors.forename: Chun-Zhong
authors.initials: CZ
authors.lastname: Wang
authors.forename: Zu-Fei
authors.initials: ZF
authors.lastname: Huang
authors.forename: Hou-Gang
authors.initials: HG
authors.lastname: Fan
authors.forename: Gang
authors.initials: G
authors.lastname: Chen