Energy decomposition based on the extended virial theorem: Hartree–Fock and second‐order Møller–Plesset results

Abstract

AbstractThe article shows how the extended virial theorem within the Born–Oppenheimer framework can be used to decompose the total energy of a molecule into atomic and diatomic energy contributions under various conditions. For the stationary points of a series of potential energy surfaces corresponding to wave functions built up by using one‐electron basis functions centered rigidly on atomic nuclei, computational results are presented at the Hartree–Fock and second‐order Møller–Plesset levels of theory. After a partial redistribution of the original diatomic energy contributions into atomic ones, the transformed diatomic energy contributions are “on the chemical scale.” It turns out that the transformed diatomic energies at the second‐order Møller–Plesset perturbation level are characteristic of the strength of the chemical bonds present in the system. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009