Long-lived short-distance intramolecular charge separation via intermolecular triplet sensitisation

Sensitised excitation of the DMN[3]DCME donor[bridge]acceptor system allows population of a triplet CT state with a microsecond lifetime in polar solv ents. This is more than five orders of magnitude longer than the lifetime o f the corresponding singlet CT state which is populated exclusively upon di rect excitation. The picture indicates the spin-forbidden nature of the cha rge recombination between the acceptor (red) to donor (green) moieties.