Multiplet Energy Level Diagrams for Cr3+ and Mn4+ in Oxides with Oh Site Symmetry Based on First-Principles Calculations

Abstract

The energy diagram representing the relationship between the multiplet energy levels of Cr3+ and the Cr-O bond length has been constructed based on first-principles calculation using CrO6 cluster with Oh symmetry. The tendency of the pressure dependence of the R line energy of ruby has been reproduced by calculation considering the configuration-dependent correction and the correlation correction. The results indicated that this tendency is dominated by the effect of correlation correction rather than the effect of covalency. In order to establish guidelines for the theoretical design of novel Mn4+-doped oxide phosphors, a similar diagram was also constructed for Mn4+ based on first-principles calculation using MnO6 cluster with Oh symmetry.