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arXiv · 1310.5366

A guided stochastic energy-domain formulation of the second order M{\o}ller-Plesset perturbation theory

Qinghui Ge·Yi Gao·Roi Baer·Eran Rabani·Daniel Neuhauser
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Abstract

We develop an alternative formulation in the energy-domain to calculate the second order M{\o}ller-Plesset (MP2) perturbation energies. The approach is based on repeatedly choosing four random energies using a non-separable guiding function, filtering four random orbitals at these energies, and averaging the resulting Coulomb matrix elements to obtain a statistical estimate of the MP2 correlation energy. In contrast to our time-domain formulation, the present approach is useful for both quantum chemistry and real-space/plane wave basis sets. The scaling of the MP2 calculation is roughly linear with system size, providing a useful tool to study dispersion energies in large systems. This is demonstrated on a structure of 64 fullerenes within the SZ basis as well as on silicon nanocrystals using real-space grids.

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Qinghui Ge, Yi Gao, Roi Baer, Eran Rabani, Daniel Neuhauser. 2013-10-20. A guided stochastic energy-domain formulation of the second order M{\o}ller-Plesset perturbation theory. https://arxiv.org/abs/1310.5366

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