DOUBLE-IONIZATION OF HEXAFLUOROBENZENE - ENERGIES REQUIRED TO POPULATE SINGLET AND TRIPLET ELECTRONIC STATES OF C6F62+

The double-ionization energies of hexafluorobenzene to singlet and tri plet electronic states of its dication have been measured by double-ch arge-transfer spectroscopy. Because the energy-loss spectrometer used has a high resolving power, more information about the electronic-stat e manifolds of C6F62+ was obtained than existed from the results of pr evious studies. The values of double-ionization energies determined ar e compared with those calculated in a previous investigation using the Green's function method, Because the predicted density of singlet and triplet states is high, only the lower energies can be identified wit h specific electronic transitions. For the higher energies, many state s could be populated to generate each of the spectral peaks observed. (C) 1997 Elsevier Science B.V.