EPR parameter factors and defect structures for ions in semiconductor

By using high-order perturbation formulas based on the two-spin–orbit (two-SO) coupling parameter mechanism and the superposition model, the g factors g and g ⊥ are calculated for Ni + ions (3d9) in a tetragonal tetrahedral crystal. By comparing the theoretical predictions with the g i values measured by electron paramagnetic resonance (EPR), the defect structures described by the anion position parameter μ , the angle θ and the tilting angle τ are estimated for the Ni + centers in CuGaSe 2 . The results indicate that the g factors of Ni + centers can be reasonably explained on the basis of the defect model.