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arXiv · 2203.12666

Diagrammatic Monte Carlo for electronic correlation in molecules: high-order many-body perturbation theory with low scaling

G. Bighin·Q. P. Ho·M. Lemeshko·T. V. Tscherbul
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Abstract

We present a low-scaling diagrammatic Monte Carlo approach to molecular correlation energies. Using combinatorial graph theory to encode many-body Hugenholtz diagrams, we sample the M{\o}ller-Plesset (MPn) perturbation series, obtaining accurate correlation energies up to n = 5, with quadratic scaling in the number of basis functions. Our technique reduces the computational complexity of the molecular many-fermion correlation problem, opening up the possibility of low-scaling, accurate stochastic computations for a wide class of many-body systems described by Hugenholtz diagrams.

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G. Bighin, Q. P. Ho, M. Lemeshko, T. V. Tscherbul. 2022-03-23. Diagrammatic Monte Carlo for electronic correlation in molecules: high-order many-body perturbation theory with low scaling. https://doi.org/10.1103/physrevb.108.045115

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