Atom-Centered Potentials with Dispersion-Corrected Minimal-Basis-Set Hartree–Fock: An Efficient and Accurate Computational Approach for Large Molecular Systems

We present a computational methodology
based on atom-centered potentials
(ACPs) for the efficient and accurate structural modeling of large
molecular systems. ACPs are atom-centered one-electron potentials
that have the same functional form as effective-core potentials. In
recent works, we showed that ACPs can be used to produce a correction
to the ground-state wave function and electronic energy to alleviate
shortcomings in the underlying model chemistry. In this work, we present
ACPs for H, C, N, and O atoms that are specifically designed to predict
accurate non-covalent binding energies and inter- and intramolecular
geometries when combined with dispersion-corrected Hartree–Fock
(HF-D3) and a minimal basis-set (scaled MINI or MINIs). For example,
the combined HF-D3/MINIs-ACP method demonstrates excellent performance,
with mean absolute errors of 0.36 and 0.28 kcal/mol for the S22x5
and S66x8 benchmark sets, respectively, relative to highly correlated
complete-basis-set data. The application of ACPs results in a significant
decrease in error compared to uncorrected HF-D3/MINIs for all benchmark
sets examined. In addition, HF-D3/MINIs-ACP, has a cost only slightly
higher than a minimal-basis-set HF calculation and can be used with
any electronic structure program for molecular quantum chemistry that
uses Gaussian basis sets and effective-core potentials.