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Title: Application of a semi‐empirical dispersion correction for modeling water clusters

The Grimme‐D3 semi‐empirical dispersion energy correction has been implemented for the original effective fragment potential for water (EFP1), and for systems that contain water molecules described by both correlatedab initioquantum mechanical (QM) molecules and EFP1. Binding energies obtained with these EFP1‐D and QM/EFP1‐D methods were tested using 27 benchmark species, including neutral, protonated, deprotonated, and auto‐ionized water clusters and nine solute–water binary complexes. The EFP1‐D and QM/EFP1‐D binding energies are compared with those obtained using fully QM methods: second‐order perturbation theory, and coupled cluster theory, CCSD(T), at the complete basis set (CBS) limit. The results show that the EFP1‐D and QM/EFP1‐D binding energies are in good agreement with CCSD(T)/CBS binding energies with a mean absolute error of 5.9 kcal/mol for water clusters and 0.8 kcal/mol for solute–water binary complexes. © 2018 Wiley Periodicals, Inc.

 
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NSF-PAR ID:
10078320
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Computational Chemistry
Volume:
40
Issue:
2
ISSN:
0192-8651
Page Range / eLocation ID:
p. 310-315
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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