Studies of the EPR Parameters and Local Structure of Co2+ in ZnO
The EPR parameters and the local structure for Co2+ in ZnO are deduced from the perturbation formulas of these parameters for a 3d7 ion in a trigonally distorted tetrahedron. The ligand orbital and spin-orbit coupling contributions are taken into account uniformly from the cluster approach in view of the covalency of the system. The impurity V3+ is found not to locate exactly on the Zn2+ site but to experience a small displacement of 0.04 Ǻ away from the ligand triangle, along the C3 axis. The theoretical EPR parameters based upon the above impurity displacement are in good agreement with the observed values.
M. Q. Kuang et al., "Studies of the EPR Parameters and Local Structure of Co2+ in ZnO", Defect and Diffusion Forum, Vols. 316-317, pp. 1-6, 2011