Beyond Walkers in Stochastic Quantum Chemistry: Reducing Error Using Fast Randomized Iteration

Samuel M. Greene, Robert J. Webber, Jonathan Weare, Timothy C. Berkelbach

Research output: Contribution to journalArticle

Abstract

We introduce a family of methods for the full configuration interaction problem in quantum chemistry, based on the fast randomized iteration (FRI) framework [Lim, L.-H.; Weare, J. SIAM Rev. 2017, 59, 547; DOI: 10.1137/15M1040827]. These methods, which we term "FCI-FRI", stochastically impose sparsity during iterations of the power method and can be viewed as a generalization of full configuration interaction quantum Monte Carlo (FCIQMC) without walkers. In addition to the multinomial scheme commonly used to sample excitations in FCIQMC, we present a systematic scheme where excitations are not sampled independently. Performing ground-state calculations on five small molecules at fixed cost, we find that the systematic FCI-FRI scheme is 11-45 times more statistically efficient than the multinomial FCI-FRI scheme, which is in turn 1.4-178 times more statistically efficient than the original FCIQMC algorithm.

Original languageEnglish (US)
Pages (from-to)4834-4850
Number of pages17
JournalJournal of chemical theory and computation
Volume15
Issue number9
DOIs
StatePublished - Sep 10 2019

ASJC Scopus subject areas

  • Computer Science Applications
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'Beyond Walkers in Stochastic Quantum Chemistry: Reducing Error Using Fast Randomized Iteration'. Together they form a unique fingerprint.

  • Cite this