Probing Photophysical Processes in Individual Multichromophoric Dendrimers by Single-Molecule Spectroscopy
Year: 2000
Type: article
Abstract: Individual multichromophoric dendrimer molecules, bearing eight perylenecarboximide chromophores at the rim, immobilized in a thin polyvinylbutyral (PVB) film were studied by far-field fluorescence microscopy. Fluorescence intensity trajectories as a function of time (transients), spectra, and decay traces were recorded separately or simultaneously. For comparison, similar measurements have been performed on a model compound containing one perylenecarboximide chromophore. Collective on/off jumps of the fluorescence intensity were observed for single dendrimer molecules, resembling previously reported collective jumps for the emission of single light-harvesting antenna systems. Spectra and decays of both non-interacting and dimer-like interacting chromophoric sites could be distinguished within an individual dendrimer. Transitions between the different spectral forms and decay times, observed for a single molecule, underline the dynamic character of the interactions among the chromophores. Evidence for a stepwise bleaching process of the multichromophoric system was found. Furthermore, the single-molecule data incontestably prove the assumptions stated in the ensemble model.
DOI: 10.1021/ja0012570
Authors: Johan Hofkens, Michael Maus, Thomas Gensch, Tom Vosch, Mircea Cotlet, Fabian Köhn, Andreas Herrmann, Klaus Müllen, Frans De Schryver
Institutions: Max Planck Institute for Polymer Research, KU Leuven
Language: English
Subfield: Physical and Theoretical Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2082009100