ESR and luminescence studies of substituted triphenylenes; excited state resonance interactions

Abstract

ESR and luminescence measurements have been performed on a series of 2-substituted triphenylenes. While methyl and methoxyl substituents perturb the electronic and ESR spectra in the expected way, aryl substitution drastically alters the electronic structure of the lowest triplet state. This perturbation is interpreted in terms of excited state resonance interactions as opposed to intramolecular energy transfer between conjugated chromophores.