Electronic structure and magnetic properties of Fe-rich ternary compounds: YFe₁₀V₂ and YFe₁₀Cr ₂

These compounds are prototypes of the Fe-rich ternary systems of ThMn ₁₂ structure which are of considerable current interest as permanent magnet materials. The electronic structure of YFe_{1 0}V₂ and YFe₁₀Cr₂ have been studied with photoemission and spin-polarized calculations. The Fe d states dominate the calculated density of states (DOS) near the Fermi energy and there is a good correspondence between the DOS and the experimental spectra. The calculated magnetization is in very good agreement with the experimental data. The calculations give a magnetic moment of ∼1 μ_B at the V or Cr site antiferromagnetically coupled to the Fe moments. This leads to a significant reduction in the average moment per Fe atom in these systems. The charge transfers are, in general, small and are mostly from V or Cr to Y atoms. These charges are used to show that the point-charge model alone cannot explain the crystal-field data.