First-Principles Calculations of Charge Transfer Transitions of Eu3+ in Y2O3 and Y2O2S

In order to investigate the ligand to metal charge transfer (LMCT) energies of Eu3+ in Y2O3 and Y2O2S, we performed first-principles calculations using EuO69- and EuY12O627+ clusters for Y2O3 and EuO4S311- and EuY15O4S334+ clusters for Y2O2S by the relativistic Discrete Variational Multi-Electron (DVME) method based on the configuration interaction (CI) approach, and constructed theoretical energy diagram. In order to improve the quantitative agreement between theoretical LMCT energies and the experimental ones, we considered the configuration-dependent correction (CDC) and the effect of lattice relaxation based on the Shannon's crystal radii. The experimental CT energies have been successfully reproduced the experimental LMCT energies of Eu3+ in Y2O3 and Y2O2S by the relativistic DVME method without any empirical parameters. In addition, we clarified the nature of states in CT transition and the assignments of the experimental CT bands of Eu3+ in Y2O3 and Y2O2S by an analysis of the configuration composition. (c) 2020 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited.