Chemical Shifts at K-Absorption Edges of Transition Metals Admixed To ZnS and ZnSe

This paper gives the experimental evidence of systematic X-ray K-absorption edge studies in an effort to analyse the effect of cation chemical shift in the group of compounds type Zn$\text{}_{1-x}$M$\text{}_{x}$A (M = Mn, Fe, Co, Ni; A = S, Se). The observed chemical shift was found practically independent of the choice of anion, whereas it revealed a noticeable decrease when passing from Mn to Zn. The effect was ascribed to the change of the 3d shell occupation. The calculations of the effective cation charge (based on the theoretical approach of Kitamura and Chen, 1991) have shown that in the case of transition metals admixed to ZnS and ZnSe there is a contribution of the 3d electrons to the overall charge transfer, which indicates that the ability of 3d electrons to participate in predominantly ionic bond decreases with 3d orbit filling.