Hydrogen chemisorption on a boron-terminated diamond (100) surface: an ab initio study

Ab initio molecular orbital theory and an atomic cluster model are used to study the structures and energetics of a boron-terminated diamond (100) surface, and hydrogen chemisorption on this surface. A 2 x 1 B-B dimer reconstruction is shown for the boron-terminated C(100) surface and the strength of B-B dimer bond is found to be stronger than that of a pi bond in the C=C dimer of a clean C(100)2 x 1 surface. Chemisorption of hydrogens on the boron-terminated C(100)2 x 1 surface breaks the surface B-B dimer bonds without activation energy which is in contrast to that on the clean C(100)2 x 1 surface. The strength of a B-H bond on the boron-terminated C(100) surface is found to be weaker than that of a C-H bond on the clean C(100) surface and so is the dehydrogenation energy. (C) 1998 Elsevier Science B.V. All rights reserved.