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arXiv · 1704.02044

A Stochastic Formulation of the Resolution of Identity: Application to Second Order Møller-Plesset Perturbation Theory

Abstract

A stochastic orbital approach to the resolution of identity (RI) approximation for 4-index 2-electron electron repulsion integrals (ERIs) is presented. The stochastic RI-ERIs are then applied to Møller-Plesset perturbation theory (MP2) utilizing a \textit{multiple stochastic orbital approach}. The introduction of multiple stochastic orbitals results in an $N^3$ scaling for both the stochastic RI-ERIs and stochastic RI-MP2. We demonstrate that this method exhibits a small prefactor and an observed scaling of $N^{2.4}$ for a range of water clusters, already outperforming MP2 for clusters with as few as 21 water molecules.

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Tyler Y. Takeshita, Wibe A. de Jong, Daniel Neuhauser, Roi Baer, Eran Rabani. 2017-04-06. A Stochastic Formulation of the Resolution of Identity: Application to Second Order Møller-Plesset Perturbation Theory. https://arxiv.org/abs/1704.02044

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