skip to main content

Title: Communication: Stochastic evaluation of explicitly correlated second-order many-body perturbation energy

A stochastic algorithm is proposed that can compute the basis-set-incompleteness correction to the second-order many-body perturbation (MP2) energy of a polyatomic molecule. It evaluates the sum of two-, three-, and four-electron integrals over an explicit function of electron-electron distances by a Monte Carlo (MC) integration at an operation cost per MC step increasing only quadratically with size. The method can reproduce the corrections to the MP2/cc-pVTZ energies of H{sub 2}O, CH{sub 4}, and C{sub 6}H{sub 6} within a few mE{sub h} after several million MC steps. It circumvents the resolution-of-the-identity approximation to the nonfactorable three-electron integrals usually necessary in the conventional explicitly correlated (R12 or F12) methods.
Authors:
 [1] ;  [2] ; ;  [3] ;  [1] ;  [4]
  1. Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)
  2. (Korea, Republic of)
  3. Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061 (United States)
  4. (Japan)
Publication Date:
OSTI Identifier:
22255273
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 140; Journal Issue: 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; ALGORITHMS; APPROXIMATIONS; BENZENE; DISTURBANCES; ELECTRONS; EVALUATION; MANY-BODY PROBLEM; METHANE; MONTE CARLO METHOD; PERTURBATION THEORY