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  • Implementation of symmetry-adapted perturbation theory based on density functional theory and using hybrid exchange–correlation kernels for dispersion terms
Title: Implementation of symmetry-adapted perturbation theory based on density functional theory and using hybrid exchange–correlation kernels for dispersion terms
We report the implementation of a symmetry-adapted perturbation theory algorithm based on a density functional theory [SAPT(DFT)] description of monomers. The implementation adopts a density-fitting treatment of hybrid exchange–correlation kernels to enable the description of monomers with hybrid functionals, as in the algorithm by Bukowski, Podeszwa, and Szalewicz [Chem. Phys. Lett. 414, 111 (2005)]. We have improved the algorithm by increasing numerical stability with QR factorization and optimized the computation of the exchange–correlation kernel with its 2-index density-fitted representation. The algorithm scales as O( N 5 ) formally and is usable for systems with up to ∼3000 basis functions, as demonstrated for the C 60 –buckycatcher complex with the aug-cc-pVDZ basis set. The hybrid-kernel-based SAPT(DFT) algorithm is shown to be as accurate as SAPT(DFT) implementations based on local effective exact exchange potentials obtained from the local Hartree–Fock (LHF) method while avoiding the lower-scaling [ O( N 4 )] but iterative and sometimes hard-to-converge LHF process. The hybrid-kernel algorithm outperforms Hartree–Fock-based SAPT (SAPT0) for the S66 test set, and its accuracy is comparable to the many-body perturbation theory based SAPT2+ approach, which scales as O( N 7 ), although SAPT2+ exhibits a more narrow distribution of errors.  more » « less
Award ID(s):
1955940
PAR ID:
10353746
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
157
Issue:
2
ISSN:
0021-9606
Page Range / eLocation ID:
024801
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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