Systematic Variations of Magnetic Properties in 3d Transition Metal Alloys

The Slater-Pauling curves, Curie-temperature Slater-Pauling curves, and the effective Bohr magneton numbers in 3d transition metal alloys are investigated on the basis of the finite-temperature theory of local environment effect, with the new results of calculations for Ni-Cr, Ni-Co and Ni-Cu alloys. It is shown that the theory explains an overall feature of the experimental data. The local environment effects on the local magnetic moments are shown to be important for the magnetization vs concentration curve in Fe-Ni alloys. The different concentration dependence between the Curie temperatures and the magnetizations is elucidated by using the effective exchange couplings between local moments. Systematic variation of the effective Bohr magneton numbers are demonstrated to be associated with the change of magnetism from the strong to the weak magnetism. Remaining problems are also discussed for the future investigations.