Ab initio calculation of phonons for bulk TiC and TiC(001)(1X1)

We present an ab initio pseudopotential study, within the local density functional approximation, of the structural and elastic properties of rock-salt TiC. The calculated structural and elastic properties of TiC are in good agreement with reported experimental values. Using the density-functional perturbation theory, the phonon spectrum and density of states are calculated. Good agreement has been found between the calculated and reported experimental dispersion curves. Following these bulk properties, we have made theoretical investigations of the atomic geometry and lattice dynamics of the TiC(001)(1X1) surface. The calculated surface structural parameters compare very well with available experimental values. Using our calculated surface phonon spectrum, we provide a detailed analysis of available experimental data from electron energy-loss spectroscopy.