We have determined the equilibrium geometry and electronic structure of the compound, ${\mathrm{BC}}_3$ using the ab initio pseudopotential local orbital approach and the local-density functional formalism. The boron-carbon compound, ${\mathrm{BC}}_3$, is a layered material with gra- phitic structure, where every fourth carbon atom is substituted by boron. The nearest-neighbor distances are predicted to be 1.42 Å for the C-C bond and 1.55 Å for the B-C bond. A monolayer of ${\mathrm{BC}}_3$ is found to be a semiconductor, and the observed metallic behavior of the bulk sample arises from interactions between neighboring layers in ${\mathrm{BC}}_3$ with AA and AB stacking. Based on total-energy calculations, we find ${\mathrm{BC}}_3$ to be less stable than graphite for the structures investigated.

• Received 4 December 1987

DOI:https://doi.org/10.1103/PhysRevB.37.3134