Journal of the Chemical Society Faraday Transactions 2 Molecular and Chemical Physics · 1979 · 84 citations · 0 references
Natural SciencesChemistryAnalytical ChemistryOrganic ChemistrySpectroscopyFluorescence SpectroscopyInorganic SpectroscopyOptical SpectroscopyPhosphorescence SpectroscopyPhotochemical KineticsPhotochemistryDielectric ConstantDielectric Constant EffectsExcited StatesNonpolar SolventsPhotophysical MechanismsSolvent Effects On FluorescenceSolvent Effects On SpectraTriplet States
Zinc tetraphenylporphine shows fairly weak fluorescence and phosphorescence but intense, long-lived triplet absorption. Benzo-1,4-quinone quenches the singlet and triplet excited states of ZnTPP and the quenching probability increases with increased polarity of the solvent. Quenching leads to formation of a complex which, for the triplet reaction in toluene, is sufficiently long-lived to be observed by flash spectroscopy. In polar solvents, quenching leads to production of separated ions, the yield being a function of the solvent dielectric constant.