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DOE OSTI · 22253647

Cubic-scaling algorithm and self-consistent field for the random-phase approximation with second-order screened exchange

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Abstract

The random-phase approximation with second-order screened exchange (RPA+SOSEX) is a model of electron correlation energy with two caveats: its accuracy depends on an arbitrary choice of mean field, and it scales as O(n{sup 5}) operations and O(n{sup 3}) memory for n electrons. We derive a new algorithm that reduces its scaling to O(n{sup 3}) operations and O(n{sup 2}) memory using controlled approximations and a new self-consistent field that approximates Brueckner coupled-cluster doubles theory with RPA+SOSEX, referred to as Brueckner RPA theory. The algorithm comparably reduces the scaling of second-order Møller-Plesset perturbation theory with smaller cost prefactors than RPA+SOSEX. Within a semiempirical model, we study H{sub 2} dissociation to test accuracy and H{sub n} rings to verify scaling.

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97 MATHEMATICS AND COMPUTINGACCURACYALGORITHMSDISSOCIATIONELECTRON CORRELATIONMEAN-FIELD THEORYPERTURBATION THEORYRANDOM PHASE APPROXIMATIONSCALINGSELF-CONSISTENT FIELD

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2014-01-07. Cubic-scaling algorithm and self-consistent field for the random-phase approximation with second-order screened exchange. https://doi.org/10.1063/1.4855255

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