Exchange‐correlation effects in interatomic energies for pure density functionals and their application to the molecular energy prediction

Abstract

AbstractIn this proof‐of‐concept paper, we show how exchange‐correlation effects can be simply recovered for interatomic energies within the interacting quantum atoms decomposition when local, gradient generalized, or meta‐gradient generalized approximations are used in density functional theory (DFT) calculations. We also demonstrate how inhomogeneity and non‐local effects can be introduced even from a pure local scheme, without resorting to any orbital information. Finally, we provide numerical evidence on a database of selected energetic molecules that this decomposition scheme can be efficiently used to build accurate models for the prediction of molecular energies from an initial “cheap” DFT calculation.