SEMI-EMPIRICAL APW CALCULATION OF THE BAND STRUCTURE OF SILICON.

A modificaton is suggested to the usual augmented-plane-wave muffin-tin approximation approach which fits exactly the measured value of the band gap of Si. The method involves one adjustable parameter which is introduced by a uniform shift of the s-like logarithmic derivatives. The results are in good agreement with those of the empirical pseudopotential method not only for the gap but also for an energy range of approximately 3 ev from the top of the valence band.