The electronic structures of NiSi2/Si(111) A- and B-type interfaces are calculated within the local-density approximation (LDA) using large supercells and the linear-muffin-tin-approximation (LMTO) full-potential and atomic-spheres approximation (ASA) methods. The Schottky-barrier heights for the two interfaces differ by 0.14 eV, in agreement with experiment. The difference is caused by a partly filled interface band present in both structures. The LDA barrier heights EF-Enu both 0.4 eV too low, and insensitive to interface relaxations and to external potentials. The correct density-functional expression for the barrier height is EF-Enu + Delta nu xc, where Delta nu xc is a nonlocal correction.
 

Physical Review Letters, 63 1168-71, 1989.