First-principles study of electronic structure of Ce3+ centres in alkaline-earth fluorides including spin-orbit and scalar relativistic effects

12th Europhysical Conference on Defects in Insulating Materials

材料科学;物理学

Popov, N.V.^1,2 ; Radzhabov, E.A.^2 ; Mysovsky, A.S.^1,2

National Research Irkutsk State Technical University, 83 Lermontov street, Irkutsk, Russia^1

A.P. Vinogradov Institute of Geochemistry SB RAS, 1a Favorsky St., Irkutsk, Russia^2

关键词: Ab initio calculations;    Alkaline earth fluorides;    Crystalline lattice;    Embedded cluster approaches;    First-principles study;    Scalar relativistic corrections;    Scalar-relativistic effects;    Structural configurations;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/80/1/012025/pdf
DOI  :  10.1088/1757-899X/80/1/012025

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

In this paper we present the results of ab initio calculations of Ce3+impurity centres in CaF2crystal. The cubic and tetragonal (interstitial fluorine compensated) configurations of centres were considered. The embedded cluster approach with polarizible crystalline lattice and CASSCF/CASPT2 methods were used to study the structural configurations and electronic properties of defects under consideration. Scalar relativistic corrections were taken into account at Douglas-Kroll-Hess level and spin-orbit effects were calculated with the RASSI approach. Calculated optical absorption spectra for cubic and tetragonal centres demonstrate good agreement with the experiment. Small symmetry breaking displacements of neighbouring ions were observed for cubic Ce3+centre ground state.