SINGLET-STATE ENERGY-LEVELS OF C2H4(2-CHARGE-TRANSFER SPECTROSCOPY() BY DOUBLE)

The double ionisation energies to lower singlet states of C2H42+ have been measured using double charge transfer spectroscopy as 30.9, 34.3, 36.2, 38.8 and 42.8 eV. These measurements are compared with the diff ering results obtained in two previous double charge transfer spectros copy investigations and with other existing data on the C2H42+ dicatio n. In particular, these results are compared with the double-ionisatio n energies and vertical-ionisation spectrum which were calculated in a previous theoretical investigation.