Using CIPSI nodes in diffusion Monte Carlo

TL;DR

This paper explores the integration of CIPSI-selected configuration interaction nodes into diffusion Monte Carlo calculations, demonstrating improved accuracy through various molecular benchmarks.

Contribution

It introduces the use of CIPSI nodes within DMC, providing a novel approach to enhance the accuracy of quantum Monte Carlo simulations.

Findings

CIPSI nodes improve DMC accuracy for diatomic molecules.

The approach performs well on the G1 benchmark set.

The method offers a promising route for accurate quantum simulations.

Abstract

Several aspects of the recently proposed DMC-CIPSI approach consisting in using selected Configuration Interaction (SCI) approaches such as CIPSI (Configuration Interaction using a Perturbative Selection done Iteratively) to build accurate nodes for diffusion Monte Carlo (DMC) calculations are presented and discussed. The main ideas are illustrated with a number of calculations for diatomics molecules and for the benchmark G1 set.