title: Photodriven Electron and Energy Transfer from Copper Phenanthroline Excited States.
abstract: Electron and energy transfer from copper 1,10-phenanthroline excited states is observed at room temperature in organic solvents. The copper phenanthroline excited states are metal-to-ligand charge-transfer in nature and have lifetimes of approximately 70-250 ns in dichloromethane solution if methyl or phenyl substituents are placed in the 2- and 9-positions of the phenanthroline ligand. The unsubstituted cuprous compound Cu(phen)(2)(PF(6)) is nonemissive under these conditions, and the excited state lifetime is <20 ns. The rate and efficiency of energy transfer to anthracene or electron transfer to viologens is reported. The cage escape efficiency of [Cu(dpp)(2)(2+), MV(+)(*)], where dpp is 2,9-diphenyl-1,10-phenanthroline, is close to unity within experimental error. Back electron transfer to ground state products occurs at the diffusion limit, 2 x 10(10) M(-)(1) s(-)(1).
authors.affiliation: Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218.
authors.forename: Mark
authors.initials: M
authors.lastname: Ruthkosky
authors.forename: Felix N.
authors.initials: FN
authors.lastname: Castellano
authors.forename: Gerald J.
authors.initials: GJ
authors.lastname: Meyer