Determination of ionization energies by the thermokinetic method

Charge transfer reactions of the type M.+ + B --> B.+ + M have been studied in order to test the applicability of the "thermokinetic" method to the determination of ionization energies (IEs). Three examples are presented with M=benzene, cyclopentanone, and vinyl alcohol. The correlation observed between the bimolecular rate constants and IE(B) allows the determination of IE(M) with a mean deviation of similar to0.02 eV with respect to spectroscopic values. One other advantage of the method is to provide ionization energies of unstable neutrals, The role of various corrective terms, and of possible geometry changes during charge transfer reactions are discussed. (C) 2001 Elsevier Science B.V.