Expeditious stochastic approach for MP2 energies in large electronic systems

TL;DR

This paper introduces a rapid stochastic method for calculating MP2 correlation energies in large electronic systems, enabling analysis of systems with thousands of electrons beyond current capabilities.

Contribution

The paper presents a novel stochastic approach that reduces the computational complexity of MP2 energy calculations for large systems using a trace formula and stochastic sampling.

Findings

Successfully applied to systems with thousands of electrons

Achieves significant speedup over traditional MP2 methods

Demonstrates effectiveness on hydrogen-passivated silicon nanocrystals

Abstract

A fast stochastic method for calculating the 2nd order M{\o}ller-Plesset (MP2) correction to the correlation energy of large systems of electrons is presented. The approach is based on reducing the exact summation over occupied and unoccupied states to a time-dependent trace formula amenable to stochastic sampling. We demonstrate the abilities of the method to treat systems of thousands electrons using hydrogen passivated silicon spherical nanocrystals represented on a real space grids, much beyond capabilities of present day MP2 implementations.