Hyperfine Field at the Tin Sites in the Heusler AlloyNi2MnSn

Abstract
The hyperfine field H(Sn) at the tin sites in Ni2MnSn has been measured by means of the Mössbauer effect at 300 and 77°K. The results, which are independent of heat treatment, have been extrapolated to 0°K to give a saturation field of ±93 ±3 kOe, in good agreement with a previous nuclear-magnetic-resonance measurement by Shinohara. H(Sn) has been calculated using the virtual-bound-state model, for a range of parameters of the theory. With the electronic ξ factor taken as 0. 04 and the magnetic moment per Mn ion as 4.0±0.1μB, agreement with experiment is obtained if the d-level occupation at Ni sites is 8. 6.