ENERGETICS USING DFT - COMPARISONS TO PRECISE ABINITIO AND EXPERIMENT

Density functional theory (DFT) has been used to analyze a large number of small molecules and to assess the quality of the energies using local and non-local functionals. The absolute DFT energies are compared to very precise ab initio results and the relative (atomization and dissociation) energies are compared to ab initio and experiment. The local approximation yields very poor energies; nevertheless, the errors follow an interesting linear trend with respect to the total energies that provides a trivial way to get corrected results. The non-local procedure used in this work yields acceptable energies and constitutes a very promising method for energetics studies.