Structural, Magnetic, and Band Structure Characteristics of the Half-Metal–Type Heusler Alloys Co₂VSi_1−xAl_x (x = 0, 0.25, 0.5, 0.75, and 1)

We investigated the structural, magnetic, and band structure properties of the quaternary full Heusler compounds Co₂VSi_1−xAl_x (x = 0, 0.25, 0.5, 0.75, and 1) by using full-potential linearized augmented-plane wave (FP-LAPW) method based on WIEN2k program The structural parameters are computed by the generalized gradient approximations (GGA) while for the electronic and magnetic properties, GGA and modified Becke–Johnson (mBj) schemes are used. It is shown that the equilibrium lattice constants and spin magnetic moment are in good agreement with the experimental values. The density of states (DOS) of Co₂VSi and Co₂VAl ternary full Heusler compounds shows a half-metallic character while for the Co₂VSi_1−xAl_x (x = 0, 0.25, 0.5, 0.75, and 1), Heusler alloys exhibit a nearly half-metallic behavior with small spin-down at the Fermi level.