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arXiv · 1704.03609

Cubic scaling algorithms for RPA correlation using interpolative separable density fitting

Jianfeng Lu·Kyle Thicke
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Abstract

We present a new cubic scaling algorithm for the calculation of the RPA correlation energy. Our scheme splits up the dependence between the occupied and virtual orbitals in $\chi^0$ by use of Cauchy's integral formula. This introduces an additional integral to be carried out, for which we provide a geometrically convergent quadrature rule. Our scheme also uses the newly developed Interpolative Separable Density Fitting algorithm to further reduce the computational cost in a way analogous to that of the Resolution of Identity method.

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Jianfeng Lu, Kyle Thicke. 2017-04-12. Cubic scaling algorithms for RPA correlation using interpolative separable density fitting. https://doi.org/10.1016/j.jcp.2017.09.012

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