First-principles local density functional investigations were made of the (111) and (¯1¯1¯1) surfaces of the cubic material. A detailed geometrical analysis was made of various reconstructions, such as (1 x 1), (2 x 1) and several (2 x 2) patterns. The stability of models with differing stoichiometries were compared as a function of the chemical potential. Stable phases were predicted for both surfaces, as a function of the N chemical potential. In the case of a B-rich environment, N-adatoms were present on the (111) surface. In the case of a N-rich environment, N-triangle patterns appeared. Two phase transitions were predicted to occur on the (¯1¯1¯1) surface. As the N chemical potential increased, the B-triangle, (2 x 1), and N-triangle reconstructions were realized. surfaces of cubic BN.

Ab initio studies of the (111) and (¯1¯1¯1) surfaces of cubic BN K.Kádas, G.Kern, J.Hafner: Physical Review B, 1998, 58[23], 15636-46