Mössbauer Effect Study of the Hyperfine Fields at the Tin Sites in Cu2MnSn, Ni2MnSn, and Pd2MnSn

The magnitude and sign of the hyperfine field at the tin site in the Heusler alloys Cu2MnSn, Ni2MnSn, and Pd2MnSn have been measured at 77 °K by means of the Mössbauer effect and found to be + 200 ± 10 kOe, + 87 ± 3 kOe, and −35 ± 2 kOe, respectively.Saturation hyperfine fields have been calculated using the virtual bound state model for a range of values of the parameters of the model. It is found that current theory is inadequate since it does not predict even the correct sign of the hyperfine field at tin sites in Cu2MnSn and Ni2MnSn.