Energy Transfer by a Hopping Mechanism in Dinuclear IrIII/RuII Complexes: A Molecular Wire?
- 7 November 2005
- journal article
- research article
- Published by Wiley in Chemphyschem
- Vol. 6 (11), 2417-2427
- https://doi.org/10.1002/cphc.200500360
Abstract
The synthesis and electrochemical and photophysical properties of a series of heterodinuclear ruthenium–iridium complexes linked by a modular para-phenylene bridge [Ir–phn–Ru]3+ (Ir=Ir(ppyFF)2bpy, Ru=Ru(bpy)3, ppyFF=2-(2,4-difluorophenyl)pyridine), bpy=2,2′-bipyridine, ph=phenylene, n=2, 3, 4, 5) are reported. The use of a high-energy iridium complex, which can act as an energy donor when coupled to the lower energy ruthenium-based component, allows the investigation of photoinduced energy transfer from the excited iridium-centre to the ruthenium fragment (energy acceptor). The rate constants of the energy-transfer processes are determined by time-resolved emission and sub-picosecond transient absorption spectroscopy. Interestingly, there is almost no decrease in transfer efficiency or rates as the length between the two chromophores (number of spacers) is increased. This “molecular wire” behavior indicates the dominance of the incoherent hopping mechanism, allowing a very fast energy transfer over long distances (with n=5 the metal-to-metal distance is estimated to be 32.5 Å). This is the first case in which such behavior is observed for metal complexes, and could lead to new development in molecular electronics.Keywords
This publication has 67 references indexed in Scilit:
- Conformationally Gated Switching between Superexchange and Hopping within Oligo-p-phenylene-Based Molecular WiresJournal of the American Chemical Society, 2005
- Rodlike Bimetallic Ruthenium and Osmium Complexes Bridged by Phenylene Spacers. Synthesis, Electrochemistry, and PhotophysicsInorganic Chemistry, 2005
- White‐Light Emission from an Assembly Comprising Luminescent Iridium and Europium ComplexesAngewandte Chemie, 2005
- Electronic energy transfer in dinuclear metal complexes containing meta-substituted phenylene unitsPure and Applied Chemistry, 2005
- Phosphorescent light-emitting electrochemical cellApplied Physics Letters, 2002
- Light emitting electrochemical devices from sequentially adsorbed multilayers of a polymeric ruthenium (II) complex and various polyanionsThin Solid Films, 1998
- Molecular Wires: Charge Transport, Mechanisms, and ControlAnnals of the New York Academy of Sciences, 1998
- Tris (2,2?-bipyridyl)ruthenium(II) electrogenerated chemiluminescence in analytical scienceMicrochimica Acta, 1997
- Palladium-Catalyzed Cross-Coupling Reactions of Organoboron CompoundsChemical Reviews, 1995
- Carbon compounds of the transition metals. Part XXV. Crystal and molecular structure of acetatobis(phenylazophenyl-2C,N′)rhodium(II)J. Chem. Soc., Dalton Trans., 1972