Synthesis, photophysical characterization, and surface photovoltage spectra of windmill-shaped phthalocyanine-porphyrin heterodimers and heteropentamers

The synthesis and characterization of three nonperipherally substituted, covalently-linked phthalocyanine-porphyrin hybrid molecules is described. The optical and photophysical properties of these compounds are studied in detail. The intramolecular energy transfer process is investigated and quantified in terms of the quantum yield of the energy transfer and is found to be highly effective in these molecules. The photophysical properties of the phthalocyanine core of these three compounds are significantly modified by the presence of the porphyrin moieties. These molecules display interesting optical-power-limiting behavior and a surface photovoltaic effect.