First-principles study of electronic structure of V 2AlC and V 2AlN

Electronic structures of the hexagonal V 2AlC and V 2AlN compounds with Cr2AlC-type structure are studied using the full-potential linearized augmented-plane-waves method within the generalized gradient approximation. The results show that the bonding is due to V-d-(C, N)-p and V-d-Al-p hybridizations, and the V-d-Al-p bonds are stronger in V 2AlN than in V 2AlC. The analysis of the band structure, charge density and total density-of-states at the Fermi level also indicated that V 2AlC and V 2AlN exhibit metallic electrical conductivity and V 2AlN should be more conductive than V 2AlC. We also find that the replacement of C with N will result in a more stable crystal structure.