EPR theoretical study of local lattice structure in ZnS:Cr2+ system

By analyzing the EPR parameters a, D and F of Cr2+ ion located at tetrahedral site in ZnS, the local structure around Cr2+ in the crystal has been investigated on the basis of the complete energy matrix for a d4 configuration in a tetragonal ligand-field within a strong-field-representation. It is shown that there exists an expansion distortion in the local lattice structure. From EPR calculation, the distortion parameters ΔR=0.13 Å and Δθ=1.417° are determined.