Photoinduced electron transfer in supramolecular ruthenium-porphyrin assemblies

EZ-C acknowledges the University of St Andrews and EPSRC (EP/M02105X/1) for financial support. DE thanks funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 700961. DJ acknowledges the European Research Council (grant: 278845) and the RFI Lumomat for financial support. We present dynamic supramolecular systems composed of a Ru(II) complex of the form of [Ru(dtBubpy)2(qpy)][PF6]2 (where dtBubpy is 4,4′-di-tert-butyl-2,2′-dipyridyl and qpy is 4,4':2',2'':4'',4'''-quaterpyridine) and zinc tetraphenylporphyrins (ZnTPP), through non- covalent interactions between the distal pyridine moieties of the qpy ligand the zinc of ZnTPP. The optoelectronic properties of the assemblies and the electronic interactions between the chromophoric units have been comprehensively characterized by computational investigations, and steady-state and time-resolved emission spectroscopy. Upon photoexcitation of ZnTPP, electron transfer to the ruthenium center is thermodynamically favorable and, as a result, strong emission quenching of both units occurs. Postprint