The relaxation dynamics of the excited state of stilbene dendrimers substituted with phenylacetylene groups

Energy migration and emitting processes of a series of dendrimers linked by a phenylacetylene group bearing stilbene as a core were investigated by steady state and time-resolved fluorescence spectroscopy. In higher generation, we confirmed efficient energy migration from peripheral moiety to a core followed by emission with high quantum yield. The kinetics of emitting state was also examined by lifetime measurement and revealed generation dependence of fluorescence decay constants. In the case of higher generation, peripheral moieties might be involved in relaxation process in the excited state in contrast to negligible interaction to the core in the ground state.