Double-ionization energies of fluorinated benzene molecules.

Results are reported of an experimental determination by double-charge transfer spectroscopy of the previously unknown double-ionization energies of the fluorinated benzene molecules C6H5F, l,2-C6H4F2, 1,3-C6H4F2, 1,4-C6H4F2, 1,2,3-C6H3F3, 1,2,4-C6H3F3, 1,3,5-C6H3F3, 1,2,3,4-C6H2F4, 1,2,3,5-C6H2F4, 1,2,4,5-C6H2F4, and C6HF5. The data are remarkably similar; the lowest double-ionization energies for all the molecules are within ±0.5 of 25.7 eV, and the data for higher energies suggest that the distributions of electronic state energies for the dications of the molecules show only small variations.