Efficient and rapid numerical evaluation of the two-electron, four-center Coulomb integrals using nonlinear transformations and useful properties of Sine and Bessel functions

  • Authors:
  • Hassan Safouhi

  • Affiliations:
  • Département de Mathématiques, Université du Québec à Montréal, C.P.8888, Succursale Centre-Ville, Montréal, Québec, Canada H3C 3P8

  • Venue:
  • Journal of Computational Physics
  • Year:
  • 2002

Quantified Score

Hi-index 31.45

Visualization

Abstract

Two-electron, four-center Coulomb integrals are undoubtedly the most difficult type involved in ab initio and density functional theory molecular structure calculations. Millions of such integrals are required for molecules of interest; therefore rapidity is the primordial criterion when the precision has been reached. This work presents an extremely efficient approach for improving convergence of semi-infinite very oscillatory integrals, based on the nonlinear D-transformation and some useful properties of spherical Bessel, reduced Bessel, and sine functions. The new method is now shown to be applicable to evaluating the two-electron, four-center Coulomb integrals over B functions. The section with numerical results illustrates the unprecedented efficiency of the new approach in evaluating the integrals of interest.