Charge disproportionation and the pressure-induced insulator-metal transition in cubic perovskite PbCrO3.

Autor:	Cheng J; Materials Science and Engineering Program and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712; Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China; Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan;, Kweon KE; Chemical Engineering and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712;, Larregola SA; Materials Science and Engineering Program and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712;, Ding Y; Advanced Photo Source, Argonne National Laboratory, Argonne, IL 60439;, Shirako Y; Materials Science and Engineering Program and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712;, Marshall LG; Materials Science and Engineering Program and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712; Department of Chemical Engineering, Northeastern University, Boston, MA 02115; and., Li ZY; Materials Science and Engineering Program and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712;, Li X; Materials Science and Engineering Program and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712;, dos Santos AM; Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831., Suchomel MR; Advanced Photo Source, Argonne National Laboratory, Argonne, IL 60439;, Matsubayashi K; Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan;, Uwatoko Y; Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan;, Hwang GS; Chemical Engineering and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712;, Goodenough JB; Materials Science and Engineering Program and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712; jgoodenough@mail.utexas.edu jszhou@mail.utexas.edu., Zhou JS; Materials Science and Engineering Program and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712; jgoodenough@mail.utexas.edu jszhou@mail.utexas.edu.
Jazyk:	angličtina
Zdroj:	Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2015 Feb 10; Vol. 112 (6), pp. 1670-4. Date of Electronic Publication: 2015 Jan 26.
DOI:	10.1073/pnas.1424431112
Abstrakt:	The perovskite PbCrO3 is an antiferromagnetic insulator. However, the fundamental interactions leading to the insulating state in this single-valent perovskite are unclear. Moreover, the origin of the unprecedented volume drop observed at a modest pressure of P = 1.6 GPa remains an outstanding problem. We report a variety of in situ pressure measurements including electron transport properties, X-ray absorption spectrum, and crystal structure study by X-ray and neutron diffraction. These studies reveal key information leading to the elucidation of the physics behind the insulating state and the pressure-induced transition. We argue that a charge disproportionation 3Cr(4+) → 2Cr(3+) + Cr(6+) in association with the 6s-p hybridization on the Pb(2+) is responsible for the insulating ground state of PbCrO3 at ambient pressure and the charge disproportionation phase is suppressed under pressure to give rise to a metallic phase at high pressure. The model is well supported by density function theory plus the correlation energy U (DFT+U) calculations.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu