First-principles Investigation of Half-metallicity and Ferrimagnet Properties of Co2ScZ (Z = As, Sb, and Bi)

Abstract

Based on the first-principles methods, the half-metallic ferrimagnet properties of Co2ScZ (Z = As, Sb, and Bi) full-Heusler alloys have been predicted by employing the full-potential linearized plane wave plus local orbital method (FP-LAPW + lo) within the framework of density functional theory (DFT) and generalized gradient approximation plus Coulomb repulsion (GGA + U) parameterization. The GGA scheme is served in this work to obtain only the equilibrium structural parameters in both paramagnetic and ferromagnetic phases, whereas the GGA + U scheme is exploited to treat the “d” electrons through electronic and magnetic properties of these Heusler alloys. The electronic structure investigation shows that all Co2ScAs, Co2ScSb, and Co2ScBi Heusler alloys are stable half metals with half-metallic gap energies (EHM) of 0.351, 1.080, and 0.836 eV, respectively. The total magnetic moment follows the generalized Slater-Pauling rule, where its value is around 2 μB for all these compounds. We have also found opposite signs between atomic magnetic moments of Co and Sc transition elements, demonstrating the ferrimagnetic behavior.