FP-LAPW investigation of electronic structure of TaN and TaC compounds

We study the structural and electronic properties of tantalum compounds, i.e. TaC and TaN, by means of accurate first principle total energy calculations using the full-potential linearized augmented plane wave plus local orbitals (FP-LAPW + lo) method. The calculations are based on density functional theory and we use the local density approximation (LDA) as well as the generalized gradient approximation (GGA) for the exchange and correlation potential. The calculated electronic structure, total energies, and equilibrium lattice constants are determined for the NaCl structure of TaC and TaN, and these results are discussed in terms of the nature of bonding found in these compounds. In both tantalum compounds studied the Ta 5d-like and N(C) 2p-like states are strongly hybridized. The values of the lattice constants, bulk moduli, and elastic constants have been calculated and are in reasonable agreement with experiment and other theoretical works.