STUDIES OF MOSSBAUER-SPECTRA FOR SM2FE17CY AND SM2FE15SI2CY

Mossbauer spectra of Sm2Fe17Cy and Sm2Fe15Si2Cy as well as their paren ts, Sm2Fe17 and Sm2Fe15Si2, respectively, have been studied. Because o f the influence of the C and Si atoms, at least five and seven subspec tra are necessary to obtain a good fit to the data for Sm2Fe17Cy and S m2Fe15Si2Cy, respectively. The effects of the C atoms on the hyperfine parameters are discussed. The hyperfine fields for the carbides incre ase on the 6c and 9d sites but decrease on the 18f and 18h sites as co mpared to those for their parents. This suggests an origin for the low er magnetization observed for Sm2Fe15Si2Cy as compared with that for S m2Fe15Si2.