EPR parameter g factors and defect structures for Ni~+ ions in CuGaSe_2 semiconductor

摘要

By using high-order perturbation formulas based on the two-spinorbit (two-SO) coupling parameter mechanism and the superposition model, the g factors g and g⊥ are calculated for Ni+ ions (3d~9) in a tetragonal tetrahedral crystal. By comparing the theoretical predictions with the gi 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 CuGaSe2. The results indicate that the g factors of Ni+ centers can be reasonably explained on the basis of the defect model.