Investigation of CIDEP effects by laser photolysis of anthraquinone

Abstract

In the photoreduction of anthraquinone by amines and alcohols strong CIDEP effects due to the triplet mechanism are observed. From the polarization the triplet quenching mechanism of the anthraquinone triplet by triethylamine could be determined as an electron transfer with k q = 3 × 10 9 M −1 s −1 and by 2-propanol as a hydrogen transfer with k L = 1.1 × 10 7 M −1 s −1. The time-resolved ESR spectra of the anthraquinone anion radical are strongly influenced by a degenerate electron exchange with a rate constant k ex = 10 7−10 8 M −1 s −1 depending on the solvent.