Hyperfine Field at the Tin Sites in the Heusler AlloyNi2MnSn

The hyperfine field $H\left(\mathrm{Sn}\right)$ at the tin sites in ${\mathrm{Ni}}_2$MnSn 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. $H\left(\mathrm{Sn}\right)$ has been calculated using the virtual-bound-state model, for a range of parameters of the theory. With the electronic $\xi$ factor taken as 0. 04 and the magnetic moment per Mn ion as $4.0\pm 0.1{\mu }_B$, agreement with experiment is obtained if the $d$-level occupation at Ni sites is 8. 6.