Assessments of DFT-based energy decomposition analysis methods for intermolecular interactions

Abstract

In this work, the analysis results of three energy decomposition analysis (EDA) methods, namely, generalized Kohn–Sham (GKS) EDA, extended transition state EDA, and density functional theory symmetry-adapted perturbation theory (DFT-SAPT), were extensively assessed for various intermolecular interactions. According to the physical meanings of their definitions, the EDA terms in the three methods can be grouped into four categories: electrostatics, exchange–repulsion/Pauli/exchange, polarization/orbital/induction, and CD (correlation/dispersion/dispersion) terms. Test examples include 1092 non-covalent interaction complexes in the standard sets (S66, PNICO23, HAL59, IL16, S66 × 8, and X40 × 10). It is concluded that despite the different basis sets and different running platforms (programs), the results of the three EDA methods are comparable. In general, except the dispersion term, all the EDA terms in the three methods are in excellent agreement. The CD term in GKS-EDA is comparable with the dispersion term in the DFT-SAPT. GKS-EDA provides another way to explore the role of electronic correlations from DFT calculations.