Chromophoric interactions in [60]fullerene-porphyrin dyads studied by spectral methods

Electronic absorption, fluorescence, photothermal and vibrational spectra of several fullerene-porphyrin dyads have been investigated. Thermal deactivation of porphyrin moieties are markedly influenced by fullerene. Participation of the excited singlet states in thermal relaxation in fullerene-porphyrin dyads is evident although the contribution of the triplet states cannot be excluded. Our experiments show the existence of a fullerene-porphyrin excimer created from the porphyrin second excited state. The observed differences in spectroscopic properties are discussed in terms of strong interaction between fullerene and porphyrins in dyads.