Pressure-induced semimetallic behavior of calcium from ab initio calculations

25th IUPAP Conference on Computational Physics

物理学;计算机科学

Magnitskaya, M.V.^1 ; Matsko, N.L.^2 ; Baturin, V.S.^2 ; Uspenskii, Yu.A.^2

L.F. Vereshchagin Institute for High Pressure Physics, Russian Academy of Sciences, 142190 Troitsk, Moscow, Russia^1

P.N. Lebedev Physical Institute, Russian Academy of Sciences, Leninskii prosp. 53, 119991 Moscow, Russia^2

关键词: Ab initio calculations;    Density of state;    Electronic spectrum;    GW approximation;    K-point sampling;    Many electron;    Metallic properties;    Spin-orbit couplings;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/510/1/012028/pdf
DOI  :  10.1088/1742-6596/510/1/012028

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

A loss of metallic properties in fcc calcium under high pressure is studied ab initio using the density functional theory (DFT) and GW approximation. It is found that a more correct description of many-electron effects given by GW method does not provide significant changes in the behavior of electronic spectrum in comparison with DFT approach. We note that the obtained width of (pseudo)gap is highly sensitive to the k-point sampling used for density of states calculation. The analysis of fcc calcium's band structure at p ∼ 20 GPa shows that the crossing of bands at the Fermi level is removed if the spin-orbit coupling is taken into account.