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  • Spin-component-scaled and dispersion-corrected second-order Møller–Plesset perturbation theory: a path toward chemical accuracy
Title: Spin-component-scaled and dispersion-corrected second-order Møller–Plesset perturbation theory: a path toward chemical accuracy
Second-order Møller–Plesset perturbation theory (MP2) provides a valuable alternative to density functional theory for modeling problems in organic and biological chemistry. However, MP2 suffers from known limitations in the description of van der Waals (London) dispersion interactions and reaction thermochemistry. Here, a spin-component-scaled, dispersion-corrected MP2 model (SCS-MP2D) is proposed that addresses these weaknesses. The dispersion correction, which is based on Grimme's D3 formalism, replaces the uncoupled Hartree–Fock dispersion inherent in MP2 with a more robust coupled Kohn–Sham treatment. The spin-component scaling of the residual MP2 correlation energy then reduces the remaining errors in the model. This two-part correction strategy solves the problem found in earlier spin-component-scaled MP2 models where completely different spin-scaling parameters were needed for describing reaction energies versus intermolecular interactions. Results on 18 benchmark data sets and two challenging potential energy curves demonstrate that SCS-MP2D considerably improves upon the accuracy of MP2 for intermolecular interactions, conformational energies, and reaction energies. Its accuracy and computational cost are competitive with state-of-the-art density functionals such as DSD-BLYP-D3(BJ), revDSD-PBEP86-D3(BJ), ωB97X-V, and ωB97M-V for systems with ∼100 atoms.  more » « less
Award ID(s):
1955554
PAR ID:
10335048
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
24
Issue:
6
ISSN:
1463-9076
Page Range / eLocation ID:
3695 to 3712
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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