The self-interaction-corrected electronic band structure of six alkali fluoride and chloride crystals

Abstract

The self-interaction-corrected form of the local density-functional approximation is used to calculate the electronic band structure of six alkali halide crystals: LiF, NaF, KF, LiCl, NaCl and KCl. Within the LCAO method, the basis functions are chosen to be Bloch sums of the occupied states of the constitution ions, plus a number of single Gaussian Bloch sums to augment the variational freedom. Without the self-interaction correction (SIC), the local density approximation predicts band gaps for the alkali halides which are 30-50% too small relative to experiment. Application of the SIC brings the agreement to within 15% for the alkali fluorides, and to within 5% for the alkali chlorides.