Mossbauer effect study of the hyperfine field at the tin site in PtMnSn

Abstract

The magnitude of the hyperfine field at the tin site in the PtMnSn alloy has been measured using the Mossbauer effect technique. The observed field is 7 kOe at 293 °K and 33 kOe at 78 °K. The sign of the field has also been determined and found to be positive. Saturation hyperfine field at the Sn-site has been estimated using the virtual bound state model of Caroli and Blandin for a range of values of the parameters of the model. It is found that the theory is inadequate since it does not predict even the correct sign of the hyperfine field at the tin site. It is suggested that the hyperfine fields observed at the tin sites in various Heusler (L2₁) and related Cl_b structure alloys could probably be understood on the basis of the model of Campbell in terms of the effective impurity potentials present at the Sn-sites in the various alloys.