Theoretical study of the electronic structure of covalent solids

Abstract

The aim of this work is to study theoretically the electronic structure of a number of ionic and covalent solids. The charges within each atomic region are calculated and a charge-transfer diagram is introduced to define a measure of the chemical bonding (ionic and (or) covalent) in these systems. The crystal-field splitting, 10 Dq, is determined for crystals with a 3d cation from the one-electron energy spectra and compared with available experiments. The transition between two of the valence levels is calculated wherever the corresponding X-ray photoelectron spectrometry or optical spectroscopic experimental data exist in the literature. Finally, the Mössbauer isomer shifts are calculated for iron containing samples.