Ab initio calculations of the reconstructed (100) surfaces of cubic silicon carbide

We have performed ab initio DFT-LDA supercell calculations for several reconstructions of the (100) surface of cubic silicon carbide. For the computations we have applied the Vienna ab initio moleculardynamic program (VAMP). We use ultrasoft Vanderbilt pseudopotentials which allow the use of an extremely small plane-wave cutoff energy. Interactions due to an artificial electric field between the two inequivalent slab surfaces are avoided by saturating one (carbon terminated) side with hydrogens. We discuss the geometries and energetics for several silicon and carbon terminated configurations (e.g, silicon-rich c(2 x 2), 2 x 1).