Ionisation potentials of benzene using the cellular method

Abstract

The authors use the variational cellular method (VCM) for the calculation of the ionisation potentials (IP) of benzene. The expected precision of the VCM is the same as that of an atomic calculation where charge and potential are spherically averaged. The calculated IP of benzene, if shifted by a constant, are in better agreement with the experiment than those of a Hartree-Fock or a multiple-scattering calculation. The shifted IP have a precision already comparable with those of a configuration interaction calculation. The constant shift of all IP is much too large, but can be understood as resulting from the assumed full symmetry of the molecular ion.