Observation of a Fluorescent Dimer of a Sulfonated Phthalocyanine¶

With very few exceptions, phthalocyanine dimers are found to be nonfluorescent. We report here the observation of a fluorescent dimer of a tetrasulfonated copper phthalocyanine in ethanol and water. Fluorescence excitation and emission spectra at room temperature and at 77 K are presented. These are consistent with the conventional model of exciton coupling in a cofacial dimer.