Six-membered Ring Chelate Complexes of Ru(II): Structural and photophysical effects
2007 (English)In: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 46, no 24, 10354-10364 p.Article in journal (Refereed) Published
The structural and photophysical properties of Ru(II)−polypyridyl complexes with five- and six-membered chelate rings were studied for two bis-tridentate and two tris-bidentate complexes. The photophysical effect of introducing a six-membered chelate ring is most pronounced for the tridentate complex, leading to a room-temperature excited-state lifetime of 810 ns, a substantial increase from 180 ns for the five-membered chelate ring model complex. Contrasting this, the effect is the opposite in tris-bidentate complexes, in which the lifetime decreases from 430 ns to around 1 ns in going from a five-membered to six-membered chelate ring. All of the complexes were studied spectroscopically at both 80 K and ambient temperatures, and the temperature dependence of the excited-state lifetime was investigated for both of the bis-tridentate complexes. The main reason for the long excited-state lifetime in the six-membered chelate ring bis-tridentate complex was found to be a strong retardation of the activated decay via metal-centered states, largely due to an increased ligand field splitting due to the complex having a more-octahedral geometry.
Place, publisher, year, edition, pages
2007. Vol. 46, no 24, 10354-10364 p.
IdentifiersURN: urn:nbn:se:uu:diva-95086DOI: 10.1021/ic7011827ISI: 000251109500039PubMedID: 17975915OAI: oai:DiVA.org:uu-95086DiVA: diva2:169162