Electronic structure and magnetism of transition-metal-stabilized YFe12-xMx intermetallic compounds.

Abstract

Self-consistent ab initio band-structure calculations using the augmented-spherical-wave method were performed for the hypothetical compounds ${\mathrm{YFe}}_{12}$ and ${\mathrm{YFe}}_{8}$${\mathit{M}}_{4}$ (M=Ti, V, Cr, Mn, Mo, and W) with the ${\mathrm{ThMn}}_{12}$ structure, in which the M atoms occupy the 8(i) crystallographic sites. We found that ${\mathrm{YFe}}_{12}$ is a weak ferromagnet: For none of the three Fe sites is the majority-spin 3d band completely occupied. Using extrapolated experimental lattice parameters, the calculated total magnetization (24.2${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$/formula-unit) and the calculated moment reduction after replacement of the Fe(i) atoms by an M atom are in good agreement with experimental data on ${\mathrm{YFe}}_{12\mathrm{\ensuremath{-}}\mathit{x}}$${\mathit{M}}_{\mathit{x}}$ (1\ensuremath{\le}x\ensuremath{\le}3) compounds. The calculated local magnetic moments are compared with the results of neutron-diffraction and M\ossbauer-spectroscopy experiments, as well as with the results of band-structure calculations on some structurally related compounds.