材料期刊网

The EPR parameters (zero-field splitting D and g factors g(\\,) g(perpendicular to)) of Co2+ ions in CdS and CdSe semiconductors are calculated from the high-order perturbation formulas based on the cluster approach for a 3d(7) ion in trigonal symmetry. These formulas include the contribution to the EPR parameters from both the spin-orbit coupling parameter of the 3d(7) ion and that of the ligand. From the calculations, the local atom-position parameters u (which are different from the corresponding values in the host crystals) for the Co2+ impurity centers in both semiconductors are estimated. The results are discussed.