A large unit cell semiempirical molecular orbital approach to the properties of solids. I. General theory

Abstract

Two semiempirical crystal orbital schemes are outlined for the calculation of the properties of perfect and defective solids. Both use periodic boundary conditions with a large unit cell (LUC) to map special points of the Brillouin zone onto the point k=0. One method involves the complete neglect of differential overlap (LUC-CNDO), the other uses intermediate neglect of differential overlap (LUC-INDO). The determination of parameter sets for the elements is discussed.