Self-consistent pseudopotential calculations for Ge and diamond (111) surfaces

The self-consistent pseudopotential method with a slab geometry is applied to electronic structure calculations of the Ge and diamond (111) surfaces. A nonlocal pseudopotential is derived and found to produce an energy band structure of bulk diamond in good agreement with other calculations and experiments. This potential is then used for the diamond surface calculations. The calculations are restricted to unrelaxed, unreconstructed surfaces. Various surface states are identified and discussed.