Dendrimer photoantenna supermolecules: Energetic funnels, exciton hopping and correlated excimer formation

Abstract A novel set of purely hydrocarbon dendrimer supermolecules has been studied, providing direct evidence of unusual photophysical and photochemical characteristics. The molecular structure gives rise to discrete exciton localization, allowing the formation of a highly photoactive antenna with a discrete energetic funnel. Steady state and fluorescence lifetime measurements have shown rapid and efficient exciton trapping at the molecular locus. Unique geometric and energetic attributes are observed which provide a means of protection from photobleaching, enhancing the longevity of these molecules. In addition, unexpected wavelength-dependent excimer formations are seen, suggesting unusual excitation-induced intermolecular interactions and dimer formations in more than one single excited state.

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