title: Photoinduced singlet charge transfer in a ruthenium(II) perylene-3,4:9,10-bis(dicarboximide) complex.
abstract: Elucidation of photoinduced charge transfer behavior in organic dye/metal hybrids is important for developing photocatalytic systems for solar energy conversion. We report the synthesis and photophysical characterization of a perylene-3,4:9,10-bis(dicarboximide) (PDI)-ruthenium(II) complex, bis-PDI-2,2'-bipyridineRu(II)Cl(2)(CN(t)butyl)(2), which has favorable energetics, ΔG(CS) ≈ -1.0 eV, for singlet electron transfer from the Ru complex to PDI. Time-resolved optical spectroscopy reveals that upon selective photoexcitation of PDI, ultrafast charge transfer (<150 fs) from the Ru complex to (1*)PDI generates the Ru(III)-PDI(-•) ion pair. The resulting vibrationally hot Ru(III)-PDI(-•) ion pair exhibits fast relaxation (τ = 3.9 ps) and charge recombination (τ(CR) = 63 ps). Our experimental and computational (DFT and TDDFT) studies show that energy-preserving photodriven singlet electron transfer can dominate in properly designed organic dye/metal complexes, making them of particular interest for use in artificial photosynthetic systems for solar fuels formation.
authors: Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, USA.
authors: Victoria L
authors: VL
authors: Gunderson
authors: Elisha
authors: E
authors: Krieg
authors: Michael T
authors: MT
authors: Vagnini
authors: Mark A
authors: MA
authors: Iron
authors: Boris
authors: B
authors: Rybtchinski
authors: Michael R
authors: MR
authors: Wasielewski