New Heusler Compounds Cr2YSb (Y=Fe, Co and Ni): Magnetic and Electronic Properties

The electronic and magnetic properties of the Cr₂YSb (Y=Co, Fe, and Ni) Heusler alloys with both CuHg₂Ti-type and AlCu₂Mn-type structures have been investigated using first-principles calculations based on density functional theory (DFT). Two nearly half-metallic ferrimagnets (HMFs), Cr₂CoSb, and Cr₂FeSb in CuHg₂Ti-type structure, are predicted. The energy gap lies in the minority spin band for both alloys. The calculated total spin magnetic moments are 2μ _B and 1μ _B per unit cell for Cr₂CoSb and Cr₂FeSb alloys, respectively, which are in good agreement with the Slater–Pauling relation. For these alloys, the magnetic moments of Y and Cr(B) are antiparallel to that of Cr(A) and all of these moments increase with increasing lattice constant. It was also found that the half-metallic properties of Cr₂CoSb and Cr₂FeSb are unaffected to the lattice distortion and the half-metallicity can be obtained within the wide range of 5.52–6.07 Å and 5.96–6.16 Å for Cr₂CoSb and Cr₂FeSb alloys, respectively.