First-principles study of electronic and dynamical properties of the TaC(001) surface

Abstract

We have made theoretical investigations of the atomic geometry, electronic structure, and lattice dynamics of the (001) surface of TaC. The atomic geometry and electronic structure for this surface have been calculated by using the generalised gradient approximation of the density functional theory and ab initio pseudopotentials. Lattice dynamical results are obtained by employing the density functional perturbation method. At least three surface phonon states appear throughout the surface Brillouin zone in the acoustic–optical gap range. Experimentally identified surface mode results are reproduced and their origin explained.