Theoretical Study Of Ground-State Zero-field Splitting Of D～5 Ions Doped In ZnS

The EPR Ground-State Zero-field Splitting of J5 ions (both Mn21 andFe' ) in ZnS crystal has been extensively studied. However, the studied results show that the calculation values of the zero-field splitting are always much less than those of the experimental findings. Up to now, this difficulty has not yet been satisfactorily removed. In the present paper, at first, we introduce method of building complete energy matrix of d' configuration ion with a trigonal symmetry as well as EPR theory. And then we calculate the ground-state zero-field splitting of ZnS : Mn: and ZnS:Fev by assuming that the sulfur ion in ZnS displays a positive effective charge and diagonalizing the complete energy matrix, and the result shows that the calculated values is in good agreement with experimental values. From this, we get an important conclusion that the sulfur ion maybe has a sp~ hybrid configuration in tetrahedral ZnS, so that -the sulfur ion displays a positive effective charge. The conclusion is also in accord with the Pauling's speculation.