Journal ArticleDOI
Excited-state quenching by proton-coupled electron transfer
Javier J. Concepcion,M. Kyle Brennaman,Jeremy R. Deyton,Natalia V. Lebedeva,Malcolm D. E. Forbes,John M. Papanikolas,Thomas J. Meyer +6 more
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TLDR
The protonated, reduced complex [Ru(bpy)2(bpzH•)]2+ functions as a H-atom reductant toward quinone or benzaldehyde with potential implications for net photochemistry and energy conversion.Abstract:
The emitting metal-to-ligand charge transfer (MLCT) excited state of [Ru(bpy)2(bpz)]2+ (bpy is 2,2‘-bipyridine; bpz is 2,2‘-bipyrazine) is reductively quenched by hydroquinone (H2Q) by proton-coupled electron transfer (PCET), most likely by concerted electron−proton transfer (EPT). The identity of the transient products ([Ru(bpy)2(bpzH•)]2+ and HQ•) and the kinetics of their formation and disappearance have been established by steady-state emission and time-resolved emission, absorption, and EPR measurements. The protonated, reduced complex [Ru(bpy)2(bpzH•)]2+ functions as a H-atom reductant toward quinone or benzaldehyde with potential implications for net photochemistry and energy conversion.read more
Citations
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Photochemistry between a ruthenium(II) pyridylimidazole complex and benzoquinone: simple electron transfer versus proton-coupled electron transfer
TL;DR: A ruthenium(II) complex with two 4,4'-bis(trifluoromethyl)-2,2'-bipyridine chelates and a 2-(2'-pyridyl)imidazole ligand was synthesized and characterized by electrochemical and optical spectroscopic means.
Journal ArticleDOI
Photophysical properties of metal complexes
TL;DR: In this article, a review summarises developments in the photophysical properties of metal complexes and their polynuclear assemblies reported in the literature for 2008 and summarizes the photodynamic properties of the metal complexes.
Journal ArticleDOI
Time-resolved spectroscopic characterization of a novel photodecarboxylation reaction mediated by homolysis of a carbon α-bond in flurbiprofen.
TL;DR: The photodecarboxylation reaction of Fp, which has been assumed to underpin its photoinduced side effects, was explored by femtosecond transient absorption, nanosecond time-resolved resonance Raman (ns-TR(3)) spectroscopic techniques, and DFT calculations were performed to facilitate the assignments of transient species.
Journal ArticleDOI
Mono- and di-nuclear Re(I) complexes and the role of protonable nitrogen atoms in quenching emission by hydroquinone
TL;DR: The results provide additional insight into the role of the protonable nitrogen atom in the photophysical properties of rhenium(i) complexes, using a dyad architecture.
Journal ArticleDOI
Kinetic isotope effect of proton-coupled electron transfer in a hydrogen bonded phenol–pyrrolidino[60]fullerene
Janneke Ravensbergen,Chelsea L. Brown,Gary F. Moore,Raoul N. Frese,Rienk van Grondelle,Devens Gust,Thomas A. Moore,Ana L. Moore,John T. M. Kennis +8 more
TL;DR: A spectroscopy study on a phenol-pyrrolidino[60]fullerene reveals a kinetic isotope effect (KIE) of 3.0, consistent with a concerted PCET mechanism.
References
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