Extended Hartree-Fock plus dispersion method accurate to a fraction of kcal/mol and applicable to dimers with hundreds of atoms

JAVIER GARCIA; SZALEWICZ, KRZYSZTOF

Philadelphia, PA

Conferencia; ACS Spring 2020 National Meeting & Expo; 2020

American Chemical Society

The Hartree-Fock plus dispersion plus first order correlation method (HFDc(1)) consists of augmenting the Hartree-Fock interaction energy with first order correlation, dispersion and exchange-dispersion contributions computed using density-functional theory based symmetry-adapted perturbation theory [SAPT(DFT)]. The variant considered used all components computed in a fully ab initio way. HFDc(1) yields accurate interaction with average errors of 0.1-0.5 kcal/mol with respect to CCSD(T) interaction energies when applied to dimers contained in benchmark sets such as S22, S66x8, IonHB, UD-ARL and NCCE3, with lower cost than similarly accurate methods such as CCSD, DLPNO-CCSD(T) or other perturbative methods. For large systems, the binding energies obtained by this method are in close agreement with the available diffusion Monte Carlo (DMC) ones. Therefore, it is an attractive method for the prediction of binding energies of dimers containing hundreds of atoms.