Local magnetic moments and hyperfine magnetic fields in Fe-M (M = Si, Sn) alloys at small metalloid concentrations

The main tendencies in the formation of local magnetic moments and hyperfine magnetic fields at Fe nuclei in Fe-Sn and Fe-Si alloys at low metalloid concentrations are analyzed on the basis of “first-principles” calculations. The results of calculations are compared with experimental data. The main differences between these alloys were proved to be due to the differences in their lattice parameters. It is shown that a significant contribution to the formation of the hyperfine field comes from the orbital magnetic moment and the Ruderman-Kittel-Kasuya-Yosida polarization, which depend on the impurity concentration and the distance to an impurity atom in the crystal lattice.