Momentum distributions and ionization potentials for the valence orbitals of benzene

The binding energy spectra and momentum distributions for several of the valence orbitals of benzene have been obtained at 1200eV using (e,2e) spectroscopy with noncoplanar symmetric kinematics. Considerable satellite structure is observed between 27.5 and 50eV. In the low electron momentum region the summed intensity of this structure amounts to one-third of the total intensity. A satellite peak at 30.5eV is assigned to the innermost 2asub(1g) valence orbital, with the majority of the high energy structure also belonging to asub(1g) orbitals. Significant satellite structure is also observed at 21.5eV and 24eV. A SCF calculation using a (9s5p/4s1p) /(4s2p/2s1p) Gaussian basis set was used to calculate the one-hole momentum profiles for the different valence orbitals. The data are in qualitative agreement with the calculated single configuration MO cross sections. The agreement with experiment is improved if account is taken of the intensity loss from the main peaks due to satellite structure. This correction to the MO cross sections is made using Green's function spectroscopic factors