SURFACE RECONSTRUCTION OF CUBIC BORON-NITRIDE (001)

Dimer- and bridge-type reconstruction on the (001) surface of cubical boron nitride (c-BN) is studied, using AM1 quantum chemical calculations of semi-infinite slabs containing 8-10 atomic layers. The optimum structure is found to be slightly buckled dimers on the boron terminated surface, but two somewhat different structures having N-N bridges spanning across second layer boron dimers are found to be energetically favoured above simple dimerization on the nitrogen terminated surface. Detailed geometries and calculated surface energies are reported for each reconstructed surface, showing that the surface energy of a boron terminated surface is significantly lower than that of the nitrogen terminated surface.