0433396 - ÚOCHB 2015 RIV GB eng J - Journal Article
Dubecký, M. - Derian, R. - Jurečka, P. - Mitas, L. - Hobza, Pavel - Otyepka, M.
Quantum Monte Carlo for noncovalent interactions: an efficient protocol attaining benchmark accuracy.
Physical Chemistry Chemical Physics. Roč. 16, č. 38 (2014), s. 20915-20923. ISSN 1463-9076. E-ISSN 1463-9084
R&D Projects: GA ČR GBP208/12/G016
Grant - others:GA ČR(CZ) GAP208/10/1742; GA MŠk(CZ) ED2.1.00/03.0058; European Social Fund(XE) CZ.1.07/2.3.00/30.0004; European Social Fund(XE) CZ.1.07/2.3.00/20.0058
Program: GA; ED
Institutional support: RVO:61388963
Keywords : basis set limit * interaction energies * CCSD(T)
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 4.493, year: 2014

Reliable theoretical prediction of noncovalent interaction energies, which are important e.g. in drug-design and hydrogen-storage applications, is one of the longstanding challenges of contemporary quantum chemistry. In this respect, the fixed-node diffusion Monte Carlo (FN-DMC) method is a promising alternative to the commonly used "gold standard" coupled-cluster CCSD(T)/CBS method due to its benchmark accuracy and favourable scaling, in contrast to other correlated wave function approaches. This work is focused on the analysis of protocols and possible trade-offs for FN-DMC estimations of noncovalent interaction energies, and proposes an efficient yet accurate computational protocol using simplified explicit correlation terms with a favorable O(N-3) scaling. It achieves results in excellent agreement (mean unsigned error similar to 0.2 kcal mol(-1)) with respect to the CCSD(T)/CBS data on a number of complexes, including benzene/hydrogen, the T-shape benzene dimer, stacked adenine-thymine complex and a set of small noncovalent complexes (A24). The high accuracy and reduced computational costs predestinate the reported protocol for practical interaction energy calculations of large noncovalent complexes, where the CCSD(T)/CBS is prohibitively expensive.
Permanent Link: http://hdl.handle.net/11104/0237721