ITERATIVE APPROACHES TO ELECTRONIC-STRUCTURE WITH AUGMENTED BASES

Combining (local) density-functional theory with molecular dynamics provides a first-principles method of studying melting, disorder, and other complex phenomena. However, there are various technical questions that have to be dealt with before such realistic attempts can be made with accurate electronic-structure calculations that use augmented bases. Here we discuss certain technical aspects of speeding up the electronic-structure codes to allow combined calculations of molecular dynamics. We present an iterative scheme to handle the generalized eigenvalue problem, discuss some aspects of these calculations where improvements are needed, and also show the equivalence of the implementations of the Cholesky decomposition and the Gram-Schmidt orthonormalization. © 1990 The American Physical Society.