Density fitting for derivatives of Coulomb integrals in ab initio calculations using mixed Gaussian and plane-wave basis

Abstract

This article presents an efficient way for evaluation of Coulomb integrals of the type (k1 (1)k2 (1)|g1 (2)g2 (2)) and their derivatives with respect to nuclear coordinates by means of density fitting. Symbols k1 andk2 stand for plane-wave functions and g1 and g2 for gaussians. The study was undertaken with the objective to accelerate electronic structure and electron scattering calculations in which a mixed Gaussian and plane-wave basis set is used. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009