Deactivation of Benzophenone Triplets via Exciplex Formation. Evidence for Dual Reaction Pathways.

摘要

The deactivation scheme of aromatic aldehyde and ketone triplets in fluid aromatic media at room temperature is dominated by the nonradiative decay pathways (Scheme I) as evidenced by very low phosphorescence quantum yields. In the past few years, very significant photokinetic work in several laboratories has shown that the nonradiative decay path in aromatic solvents, in fact, is dominated by a bimolecular quenching process, step 5, that proceeds via a short-lived complex having some charge transfer character. (Author)