Empirical corrections and pair interaction energies in the fragment molecular orbital method

TL;DR

This paper develops and evaluates empirical corrections and pair interaction energy analysis within the fragment molecular orbital (FMO) method, enhancing its accuracy for complex molecular systems including proteins.

Contribution

It introduces an extended FMO approach with empirical corrections and pair interaction energy decomposition, improving accuracy and analysis capabilities.

Findings

FMO with empirical corrections shows improved accuracy for protein systems.

Pair interaction energies vary with different approaches, providing detailed insights.

The method is validated on water clusters and protein-ligand complexes.

Abstract

The energy and analytic gradient are developed for FMO combined with the Hartree-Fock method augmented with three empirical corrections (HF-3c). The auxiliary basis set approach to FMO is extended to perform pair interaction energy decomposition analysis. The FMO accuracy is evaluated for several typical systems including 3 proteins. Pair interaction energies computed with different approaches in FMO are compared for a water cluster and protein-ligand complexes.