All electron and pseudopotential ab initio Hartree-Fock computations were performed on a molecular system designed to model a carbon atom on the (111) surface of diamond. The computations performed by a number of basis sets agree in forecasting a relaxation of the dangling bond carbon atom much lower than that obtained by semi-empirical computations (0.1 versus 0.2 to 0.3Å). Minimal basis set computations performed for a larger model cluster containing three surface atoms result in a comparable mean relaxation when also reconstruction was allowed.

A Theoretical Study of Relaxation and Reconstruction of the (111) Surface of Diamond. V.Barone, F.Lelj, N.Russo, M.Toscano, F.Illas, J.Rubio: Surface Science, 1985, 162[1-3], 169-74