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Pressure-induced spin transition and site-selective metallization in CoCl₂.

ABSTRACT: The interplay between spin states and metallization in compressed CoCl₂ is investigated by combining diffraction, resistivity and spectroscopy techniques under high-pressure conditions and ab-initio calculations. A pressure-induced metallization along with a Co²⁺ high-spin (S?=?3/2) to low-spin (S?=?1/2) crossover transition is observed at high pressure near 70?GPa. This metallization process, which is associated with the p-d charge-transfer band gap closure, maintains the localization of 3d electrons around Co²⁺, demonstrating that metallization and localized Co²⁺ -3d low-spin magnetism can coexist prior to the full 3d-electron delocalization (Mott-Hubbard d-d breakdown) at pressures greater than 180?GPa.

SUBMITTER: Barreda-Argueso JA

PROVIDER: S-EPMC6443712 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Pressure-induced spin transition and site-selective metallization in CoCl2.

Barreda-Argüeso Jose A JA Nataf Lucie L Aguado Fernando F Hernández Ignacio I González Jesús J Otero-de-la-Roza Alberto A Luaña Víctor V Jia Yating Y Jin Changqing C Kim Bongjae B Kim Kyoo K Min Byung I BI Heribert Wilhem W Jephcoat Andrew P AP Rodríguez Fernando F

Scientific reports 20190401 1

The interplay between spin states and metallization in compressed CoCl2 is investigated by combining diffraction, resistivity and spectroscopy techniques under high-pressure conditions and ab-initio calculations. A pressure-induced metallization along with a Co2+ high-spin (S = 3/2) to low-spin (S = 1/2) crossover transition is observed at high pressure near 70 GPa. This metallization process, which is associated with the p-d charge-transfer band gap closure, maintains the ...[more]

PMID: 30931950

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