Improved SCF convergence acceleration

Abstract

An improved version of the direct inversion in the iterative subspace algorithm is developed. The method is significantly more efficient than the previous version, and is applicable to intrinsically divergent or slowly convergent cases. Comparisons indicate that the method is superior to the recently proposed quadratically convergent (QC–SCF) method of Bacskay. Copyright © 1982 John Wiley & Sons, Inc.