Dresden 2006 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 25: POSTER Electronic Structure and Spectroscopy
CPP 25.11: Poster
Donnerstag, 30. März 2006, 17:00–19:00, P2
Electronic excitation energy transfer in individual donor-acceptor dyads — •Remi Metivier1, Florian Feist1, Fabian Nolde2, Klaus Müllen2, and Thomas Basché 1 — 1Institut für Physikalische Chemie, Johannes Gutenberg-Universität Mainz — 2Max Planck-Institut für Polymerforschung, Mainz
We have studied a new class of structurally well-defined donor-acceptor dyades which exhibit efficient unidirectional energy transfer.The dyads are formed by connecting a variable number of donor chromophores (peryleneimide/perylenediimide) to an acceptor chromophore (terrylenediimide) through a rigid poly(phenylene) linker. In a first set of experiments a linear dyad was investigated, where the donor and the acceptor are linked by a p-terphenyl spacer. Fluorescence emission spectra showed acceptor emission only indicating highly efficient energy transfer. Single molecule spectroscopy at low temperature (1.4K) offers the possibility to directly extract the energy transfer rates from the line widths of the donor fluorescence excitation spectra. The distribution of energy transfer times was centered around 5 picoseconds. Comparison to a distribution calculated by assuming a Förster mechanism showed that an additional through-bond interaction might play a role in this bichromophoric dyad. The second multichromophoric system studied is a polyphenylene dendrimer in which four peripheral donor chromophores are build around a central acceptor core. Besides measuring energy transfer rates for individual donor chromophores within an isolated aggregate, we will also show that the orientation of the donor chromophores can be estimated from the distribution of transfer times.