First-principles local-density-functional calculations were made of the structural and electronic properties of clean and hydrogenated diamond (111) surfaces with one and three dangling bonds (1db, 3db), respectively. For the clean 1db-surface a (2 x 1) reconstruction was predicted, with symmetrical very slightly buckled dimers at the surface, and a stronger buckling in the deeper layers. Hydrogenation led to a complete de-reconstruction of the (111)-1db surface. For the 3db-surfaces a comparative study was made of the (2 x 1) and (√3 x √3) reconstructions and it was found that the (2 x 1) structure had a slightly lower energy for both the clean and the hydrogenated surfaces.

Surface Reconstruction and Electronic Properties of Clean and Hydrogenated Diamond (111) Surfaces. G.Kern, J.Hafner, J.Furthmüller, G.Kresse: Surface Science, 1996, 357-358, 422-6