Role of Orthogonalization in the Determination of Valence States in Crystals

Publisher Website
Google Scholar
Abstract
The orthogonalization process used in the method of orthogonalized plane waves (OPW) and in the pseudopotential method of Phillips and Kleinman (PK) is investigated. It is shown that the sole effect of this procedure is the introduction of proper core behavior into the wave function. A more direct method is shown to give the same result more simply than OPW and with better accuracy in the case that the core functions are not well known. The alternative formulation can also be used to derive the PK pseudopotential and leads to a deeper insight into its meaning.