Density functional theory study of structural and electronic properties of group V transition metal carbides

The structural and electronic properties of group V transition metal carbides: VC, NbC and TaC are studied using density functional theory with generalized gradient approximation for the exchange and correlation potential. Lattice constants, bulk moduli, elastic constants, energy band diagrams, density of states of the carbides are reported and their trends are discussed. From the band diagrams, the band separation, zone-centre d band splitting, non metal p and s band splitting, width of 2p band, and 4d band explains the insight of electronic structure of these compounds. (author)