LOCAL LATTICE STRUCTURE AROUND IMPURITY IONS IN IIA-VIB COMPOUNDS OF NACL STRUCTURE

Results of fluorescence XAFS measurements for Mn in SrS and Pb in CaS as well as the absorption spectra of MnS and PbS are reported. The evi dence of the similarity of the local structure around Pb ions in CaS a nd that of pure PbS is clearly shown by the analysis of the XAFS spect ra. However, the structure around Mn ions in SrS is considerably defor med and not similar with that of MnS. The results suggest that the loc al structure of the impurity ions is very much dependent on the differ ence of the size of impurity ions and that of the host ions.