Nonlocal-density approximation to exchange and correlation: Effect on the silicon band structure

We present the results of a self-consistent pseudopotential band-structure calculation for silicon using a nonlocal-density approximation for the exchange and correlation potential. The valence bands are very close to the corresponding local-density results; however, the conduction bands are shifted to higher energies with respect to the valence-band edge. Thus the agreement with experiment is substantially improved. In particular, the indirect band gap is reproduced.