Pure Appl. Chem., 2006, Vol. 78, No. 12, pp. 2261-2266
Probing molecular properties and the role of the environment at the single-molecule level
Abstract: Evidence for intramolecular photoinduced electron transfer (ET) in synthetic systems consisting of a triphenylamine-perylenediimide donor-acceptor dendrimer or a triphenylamine-peryleneimide dendrimer at the ensemble and single-molecule (SM) level is presented. Moreover, for the first time a direct observation of the forward as well as the backward ET step is made in a single emitting entity. Fluctuations in the values of the rate constants for forward and backward ET were observed, induced by the local environment as well as by conformational changes of the dendrimer itself. The results obtained in a weakly coupled system can also be extended to a strongly coupled donor-acceptor system based on peryleneimide and penta-phenylene.