Half-metallic magnetism of Co2CrX (X=As, Sb) Heusler compounds: An ab initio study

In this study, we present the electronic, magnetic, and structural properties of two novel half-metallic full-Heusler compounds, Co2CrAs and Co2CrSb, in cubic L2(1) geometry. The calculations are based on the density functional theory within plane-wave pseudopotential method and spin-polarized generalized gradient approximation of the exchange-correlation functional. The electronic band structures and density of states of the systems indicate half-metallic behavior with vanishing electronic density of states of minority spins at Fermi level, which yields perfect spin polarization. The calculated magnetic moments of both systems in L2(1) structure are 5.00 mu(B), which are largely localized on the chromium site. The energy gaps in minority spin states are restricted by the 3d-states of cobalt atoms on two different sublattices. The formation enthalpies for both structures are negative indicating stability of these systems against decomposition into stable solid compounds. (C) 2010 Elsevier B.V. All rights reserved.