The covalent effect on the energy levels of d3d3 ions in tetragonal compounds

For d3d3 ions in covalent compounds with tetragonal symmetry, this paper presents a complete energy matrix, in which the different covalence of t2t2 and ee orbitals is considered not only in the electrostatic repulsions part of energy matrix elements but also in the crystal-field potential part of energy matrix elements. With taking and no taking the crystal field parameter B000 into account, the effect of covalence on the energy levels of d3d3 ions system were investigated, respectively. The investigation shows that it is very necessary for considering the different covalence of t2t2 and ee orbitals in both electrostatic repulsions part and crystal-field potential part when the optical properties of d3d3 ions in strong covalent compounds with tetragonal symmetry is investigated. On the other hand, the crystal field parameter B000 has a significant effect on the energy levels, and should be considered in investigations of d3d3 ions in strong covalent compounds with tetragonal symmetry. Application to calculating the energy levels for Co2+ in CdGa2Se4, the calculated results are in agreement with the experiment data.