Temperature-induced switching of the mechanism for intramolecular energy transfer in a 2,2':6'2''-terpyridine-based Ru(II)-Os(II) trinuclear array

A study was carried out to establish the mechanism for intramolecular triplet energy transfer and to enquire if the rate may be modulated by changes in torsion angle. It was found that the involvement of an intermediate charge-transfer (CT) state does not decay directly to the ground state but is favored by a polar solvent and ambient temperature.