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Title: Electrostatically embedded symmetry-adapted perturbation theory
Symmetry-adapted perturbation theory (SAPT) is an ab initio approach that directly computes noncovalent interaction energies in terms of electrostatics, exchange repulsion, induction/polarization, and London dispersion components. Due to its high computational scaling, routine applications of even the lowest order of SAPT are typically limited to a few hundred atoms. To address this limitation, we report here the addition of electrostatic embedding to the SAPT (EE-SAPT) and ISAPT (EE-ISAPT) methods. We illustrate the embedding scheme using water trimer as a prototype example. Then, we show that EE-SAPT/EE-ISAPT can be applied for efficiently and accurately computing noncovalent interactions in large systems, including solvated dimers and protein–ligand systems. In the latter application, particular care must be taken to properly handle the quantum mechanics/molecular mechanics boundary when it cuts covalent bonds. We investigate various schemes for handling charges near this boundary and demonstrate which are most effective in the context of charge-embedded SAPT.  more » « less
Award ID(s):
1955940
PAR ID:
10566308
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
American Institute of Physics Publishing
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
161
Issue:
13
ISSN:
0021-9606
Page Range / eLocation ID:
134112
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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