Calculated ground-state properties of silicon carbide

Abstract

The local density functional technique is applied to the ab initio calculation of ground-state properties of cubic silicon carbide. Norm-conserving pseudopotentials are used with the atomic numbers of the elements as the only inputs. Results for the equation of state, real-space distribution of electronic charge and selected phonons are presented. The pressure derivative of the bulk modulus, B'₀, is predicted and the Gruneisen parameters describing the pressure variation of the phonon modes are calculated. More than 1000 plane waves per unit cell are needed to achieve satisfactory convergence of these quantities. The calculated values agree with experiment to within a few per cent. The features of the electronic charge distribution are discussed, as is its variation under applied pressure.