MOSSBAUER-EFFECT OF CO-DOPED OR MN-DOPED BETA-FESI2

The Mossbauer effect of Fe-57 in transition metal (Co or Mn)-doped bet a-FeSi2 was measured at room temperature so as to examine the local at omic structure around iron atoms. From the analysis of Mossbauer spect ra, it is disclosed that (1) many vacancies exist in site I in undoped beta-FeSi2; and (2) Mn atoms occupy I sites in beta-FeSi2 whereas Co atoms occupy II sites. Isomer shifts of I sites and II sites in Co- or Mn-doped beta-FeSi2 are found to be greater than those in beta-FeSi2.