Effect on the EPR and local lattice structure distortion of V³⁺ ion doping corundum crystal: three models studied

Abstract

This paper reports on the application of conventional models (the displacement model and the elongation model) and the four-parameter model in detecting the local molecular structure of a coordination complex. By diagonalizing the complete energy matrices, the EPR parameters and optical spectra as well as the local distortion structure for V³⁺ ion in the Al₂O₃ : V³⁺ system have been studied using the three models. The four-parameter model is shown to provide a significant improvement over the conventional models. Based on these calculations, it was found that when V³⁺ is doped in Al₂O₃, the distance between upper and lower ligand oxygen plane increases by 0.16097 Å and the shifts of O²⁻ ions in the upper and lower ligand oxygen planes expand by 0.07076 Å and 0.004066 Å, respectively. To understand the detailed physical and chemical properties of the doped Al₂O₃, the contributions of the spin-orbit coupling to the zero-field splitting for V³⁺ ion are investigated.

Keywords:

• three models
• EPR and optical spectra
• local lattice structure distortion
• Al₂O₃ : V³⁺ system

Acknowledgements

This work was supported by the National Natural science Foundation of China (No. 10774103) and the Doctoral Education Fund of Education Ministry of China (No. 20050610011).