Density-Fitting Approximations to the Electron Repulsion Integrals
نویسنده
چکیده
Here we will follow some of the presentation from Werner, Manby, and Knowles. 1 Density fitting is a way to approximate the usual two-electron integrals, (pq|rs) = dr 1 dr 2 φ p (r 1)φ q (r 1) 1 r 12 φ r (r 2)φ s (r 2), (1) where we have assumed real orbitals. We may also consider this electron repulsion integral as the repulsion between two generalized electron densities,
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