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DOE OSTI · 1695748

Range-separated stochastic resolution of identity: Formulation and application to second-order Green’s function theory

Dou, Wenjie·Chen, Ming·Takeshita, Tyler Y.·Baer, Roi·Neuhauser, Daniel·Rabani, Eran
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Abstract

We develop a range-separated stochastic resolution of identity (RS-SRI) approach for the four-index electron repulsion integrals, where the larger terms (above a predefined threshold) are treated using a deterministic RI and the remaining terms are treated using a SRI. The approach is implemented within a second-order Green’s function formalism with an improved O(N 3 ) scaling with the size of the basis set, N. Moreover, the RS approach greatly reduces the statistical error compared to the full stochastic version [T. Y. Takeshita et al., J. Chem. Phys. 151, 044114 (2019)], resulting in computational speedups of ground and excited state energies of nearly two orders of magnitude, as demonstrated for hydrogen dimer chains and water clusters.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYcorrelation energygreen-functions techniqueperturbation theorystatistical fluctuationsstochastic processes

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Dou, Wenjie, Chen, Ming, Takeshita, Tyler Y., Baer, Roi, Neuhauser, Daniel, Rabani, Eran. 2020-08-21. Range-separated stochastic resolution of identity: Formulation and application to second-order Green’s function theory. https://doi.org/10.1063/5.0015177

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