The photophysics of a series of Ru(II) dyads based on the 2-(1-pyrenyl)-1H-imidazo[4,5-f][1,10]-phenanthroline ligand was investigated. The ability of these metal complexes to intercalate DNA and induce cell death upon photoactivation makes them attractive photosensitizers for a range of photobiological applications, including photodynamic therapy. In the present study, time-resolved transient absorption and emission spectroscopy were used to interrogate the photoinduced processes that follow metal-to-ligand charge transfer excitation of the complexes in solution. It was found that energy transfer to pyrene-localized intraligand triplet states, facilitated by torsional motion of the pyrene moiety relative to the imidazo[4,5-f][1,10]phenanthroline ligand, was an important relaxation pathway governing the photophysical dynamics in this class of compounds. Biphasic decay kinetics were assigned to spontaneous (pre-equilibrium) and delayed emission, arising from an equilibrium established between (3)MLCT and (3)IL states. TDDFT calculations supported these interpretations.
Autorzy
- Christian Reichardt,
- Mitch Pinto,
- Maria Wachtler,
- Mat Stephenson,
- Stephan Kupfer,
- Tariq Sainuddin,
- prof. dr hab. Julien Guthmuller link otwiera się w nowej karcie ,
- Sherri A. Mcfarland,
- Benjamin Dietzek
Informacje dodatkowe
- DOI
- Cyfrowy identyfikator dokumentu elektronicznego link otwiera się w nowej karcie 10.1021/acs.jpca.5b01737
- Kategoria
- Publikacja w czasopiśmie
- Typ
- artykuł w czasopiśmie wyróżnionym w JCR
- Język
- angielski
- Rok wydania
- 2015