A new approach to theab initio energy of the homodesmic reaction for the resonance energy of benzene

Summary A scheme of the basis set superposition error (BSSE) correction is first proposed and introduced to determine theab initio energy of the homodesmic reaction for the resonance energy of benzene. Calculations with 6-31G*(5D) and 6-31G*(6D) basis sets at the complete fourth-order Møller-Plesset perturbation level furnish the energy value of 21.35 kcal/mol after the correction, which is in complete agreement with the experimental value of 21.3±0.2 kcal/mol. The energy values at the lower theoretical levels are generally underestimated but they are superior to the uncorrected values. The inclusion of triple excitations displays the dominant contribution of the correlation energy. Detailed analysis of the results reveals some of the similarities between the homodesmic reaction of benzene and the interaction of van der Waals molecule, which provides further justification of the BSSE correction scheme presented in this study.