Intramolecular Charge Transfer Luminescence of a donorethylsubstituted pyridinium ion

The dimethoxyphenyl-ethyl-substituted pyridinium ion 1 shows a long-wave absorption and fluorescence, which are attributed to an intramolecular electron donor-acceptor complex. In contrast to electrically neutral complexes the fluorescence quantum yield of 1 in polar solvents is comparatively high and the radiative decay time is rather small. The excited complex can also be generated by electrochemical methods.