Magnetic Properties of Interstitial Compounds Sm(Fe11Ti)X1-δ (X=N, C)

Abstract

New interstitial compounds Sm(Fe11Ti)X1-δ (X =N; δ=0.8 and X=C; δ=0.7) have been made by heating a fine powder of Sm(Fe11Ti) in nitrogen or butane, respectively. In the nitride, there is a 3% increase in unit cell volume, approximately 10% increase in the iron moment (estimated from 57Fe Mössbauer spectra) and a 185 K increase in the Curie temperature to 769 K. The uniaxial anisotropy is destroyed, however and A20≫10Ka0-2 in the nitride. These effects are compared with those in R2Fe17 nitrides or carbides and the differences are explained qualitatively in terms of Coehoorn's model considering the configuration of interstitial atoms around thd rare earth.