Mössbauer effect studies of Dy(Fe0.4Co0.6−xNix)2 intermetallics

A consequence of Co/Ni substitution in the intermetallics Dy(Fe0.4Co0.6−xNix)2 was tested in this paper. Fe57 Mössbauer effect measurements for the intermetallic system were carried out at 4.2 K and the determined hyperfine interaction parameters as functions of composition are reported. The magnetic hyperfine field as well as the Curie temperature is strongly reduced with a composition parameter x. Band structure calculations using the full-potential linearized augmented plane waves (FLAPW) method were performed. Some properties of the 3d bands of the Fe, Co and Ni constituents are discussed. The 3d band splitting energies and the magnetic moments of transition metals reduce with x. The experimentally determined magnetic hyperfine field correlates linearly with the calculated stoichiometrically weighted magnetic moment of 3d atoms and correlates linearly with the weighted splitting energy between 3d subbands. The Curie temperature changes nonlinearly with the squared magnetic hyperfine field or with the calculated squared weighted splitting energy between 3d subbands.