Optimal selection of partial charge calculation method for rapid estimation of enthalpies of formation from Hartree-fock total energy

The rapid estimation of basis set error and correlation energy from partial charges (REBECEP) method is discussed which is improved further in several ways by introducing total energies derived from experimental enthalpies of formation instead of G3 energies in the fitting procedure. It was found the REBECEP method performed better for the 117 molecules with a moderate 6-31G(d) basis set than the B3LYP method with large 6-311+G(3df,2p) basis set.