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Updated: Mar 7, 2026
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Published on: May 10, 2021
A-Site and B-Site Charge Orderings in an s-d Level Controlled Perovskite Oxide PbCoO3
Yuki Sakai1, Junye Yang2, Runze Yu3
1Kanagawa Academy of Science and Technology , KSP, 3-2-1 Sakado, Takatsu-ku, Kawasaki City, Kanagawa 213-0012, Japan.
Abstract:
Perovskite PbCoO3 synthesized at 12 GPa was found to have an unusual charge distribution of Pb2+Pb4+3Co2+2Co3+2O12 with charge orderings in both the A and B sites of perovskite ABO3. Comprehensive studies using density functional theory (DFT) calculation, electron diffraction (ED), synchrotron X-ray diffraction (SXRD), neutron powder diffraction (NPD), hard X-ray photoemission spectroscopy (HAXPES), soft X-ray absorption spectroscopy (XAS), and measurements of specific heat as well as magnetic and electrical properties provide evidence of lead ion and cobalt ion charge ordering leading to Pb2+Pb4+3Co2+2Co3+2O12 quadruple perovskite structure. It is shown that the average valence distribution of Pb3.5+Co2.5+O3 between Pb3+Cr3+O3 and Pb4+Ni2+O3 can be stabilized by tuning the energy levels of Pb 6s and transition metal 3d orbitals.
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