6533b830fe1ef96bd1297200
RESEARCH PRODUCT
Polychromatic femtosecond fluorescence studies of metal–polypyridine complexes in solution
Ahmed M. El-zohryOlivier BrämFabrizio MessinaMajed CherguiAndrea Cannizzosubject
Aqueous solutionChemistryFluorescence up-conversionSettore FIS/01 - Fisica SperimentaleGeneral Physics and AstronomyIntersystem crossingMetal–polypyridine complexes; IVR; Internal conversion; Intersystem crossing; Ultrafast; Fluorescence up-conversionPhotochemistryFluorescencePhotoinduced electron transferIntersystem crossingInternal conversionUltrafastExcited stateIntramolecular forceFemtosecondIVRMetal–polypyridine complexePhysical and Theoretical ChemistrySolvent effectsdescription
Femtosecond-resolved broadband fluorescence studies are reported for[ M(bpy)(3)](2+) (M = Fe, Ru), RuN3 and RuN719 complexes in solution. We investigated the pump wavelength dependence of the fluorescence of aqueous [ Fe(bpy)(3)](2+) and the solvent and ligand dependence of the fluorescence of Ru-complexes excited at 400 nm. For all complexes, the (MLCT)-M-1 fluorescence appears at zero time delay with a mirror-like image with respect to the absorption. It decays in <= 30-45 fs due to intersystem crossing to the (MLCT)-M-3 states, but a longer lived component of similar to 190 fs additionally shows up in RuN719 and RuN3. No solvent effects are detected. The very early dynamics are characterized by internal conversion (IC) and intramolecular vibrational redistribution (IVR) processes on a time scale which we estimate to <= 10 fs using the (MLCT)-M-1 lifetime as an internal clock. (C) 2011 Elsevier B. V. All rights reserved.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2011-12-03 |