Closed formulae for (1s|1s), Slater two‐center integrals, using the three‐center nuclear attraction integral program in spherical coordinates

Abstract

ABSTRACT:The strategy of using expansions in spherical harmonics of displaced Slater-type (exp (Ϫ␣x) ) orbitals to evaluate multicenter molecular integrals is applied to three-centered nuclear attraction integrals (potential due to the product of separated Slater-type orbitals). Closed formulae are produced for nine terms of an infinite series for interior region, (inside Ϫ ipot) r 2 Ͻ a, and 14 terms for Exterior Region, (outside Ϫ epot) r 2 Ͼ a. The value a ϭ 2 is chosen for the interior region and r ϭ 14 for the exterior region. Our focus is to obtain a closed formula for the Slater formula.

Use of Guseinov's One-Center Expansion Formulae and Löwdin α Radial Function in Calculation of Two-Center Overlap Integrals over Slater Type Orbitals with Noninteger Principal Quantum Numbers

“…[15,16]). For the calculation of S nlλ,n l λ (ζ, ζ ; R) we use the Löwdin α radial function [10] in the following form [17][18][19][20][21][22]:…”