Monte Carlo MP2-F12 for Noncovalent Interactions: The C60 Dimer

Autor:	Alexander E. Doran, David L. Qiu, So Hirata
Rok vydání:	2021
Předmět:	Superposition principle Orders of magnitude (time) Chemistry Monte Carlo method Autocorrelation Intermolecular force Binding energy Physics::Atomic and Molecular Clusters Statistical physics Physical and Theoretical Chemistry Imaginary time Basis set
Zdroj:	The Journal of Physical Chemistry A. 125:7344-7351
ISSN:	1520-5215 1089-5639
DOI:	10.1021/acs.jpca.1c05021
Popis:	A scalable stochastic algorithm is presented that can evaluate explicitly correlated (F12) second-order many-body perturbation (MP2) energies of weak, noncovalent, intermolecular interactions. It first transforms the formulas of the MP2 and F12 energy differences into a short sum of high-dimensional integrals of Green's functions in real space and imaginary time. These integrals are then evaluated by the Monte Carlo method augmented by parallel execution, redundant-walker convergence acceleration, direct-sampling autocorrelation elimination, and control-variate error reduction. By sharing electron-pair walkers across the supermolecule and its subsystems spanned by the joint basis set, the statistical uncertainty is reduced by one to 2 orders of magnitude in the MP2 binding energy corrected for the basis-set incompleteness and superposition errors. The method predicts the MP2-F12/aug-cc-pVDZ binding energy of 19.1 ± 4.0 kcal mol-1 for the C60 dimer at the center distance of 9.748 A.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::e76d3d8ba4100e12af606cf93ee99fc0 https://doi.org/10.1021/acs.jpca.1c05021 Zobrazit plný text záznamu