Vertical ionization potentials and CTTS energies for anions in water and acetonitrile

The photoelectron emission threshold energy values, Et, are collected for eleven anions in water and five anions in acetonitrite. The Et values are found to be linearly correlated with the charge-transfer-to-solvent (CTTS) energies, ECTTS. This correlation can be used to find CTTS bands for some of the anions for which it is difficult to distinguish the bands from the intramolecular transitions such as π → π∗. The difference, Et - ECTTS, is found to depend on the kind of the anion not being consistent with the result reported by Burg and Delahay.