Photochemical depassivation of hydrogenated (100) nitrogen surface of cubic boron nitride

The passivation of the nitrogen top-layered (100) surface of cBN by hydrogen was theoretically predicted recently to be related to the difficulty of chemical vapor deposition of cubic boron nitride. The possibility of photochemical depassivation of this surface was suggested by the anti-bonding nature of the surface H-N bonds at the lowest unoccupied molecular orbital; that was demonstrated by AM1 molecular orbital calculations using large cBN clusters such as B30N32H64(2+) and B30N32H62(2BH(3)).