ORGN 4 |
| Christopher J. Bardeen1, Alexis L. Thompson1, Todd Martinez1, S Thayumanavan2, and K. R. Justin Thomas2. (1) Department of Chemistry, University of Illinois, 600 S. Mathews Ave., Urbana, IL 61801, (2) Department of Chemistry, University of Massachusetts, 701 Lederle Graduate Research Tower, 710 North Pleasant St., Amherst, MA 01003-9336 |
| We describe experimental and theoretical results on energy and charge transfer through cojugated networks constructed using phenylacetylene bridging groups. Efficient energy transfer through dendrimers composed of phenylacetylene segments is shown to be the result of enhanced through-bond coupling that occurs on the excited state. This enhanced coupling, which results from the interplay of nuclear relaxation and electronic coupling, helps cancel out the meta-effect which decouples these segments in the ground electronic state. Both theory and experiment confirm this effect. The effects of meta- and para-substitution on excited state charge transfer in donor-acceptor complexes are also investigated. Prospects for using the excited state switching of through-bond electronic interactions for gating of charge or energy transfer events will be discussed. |
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Molecular Mimicry of Photosynthesis
8:30 AM-12:00 PM, Sunday, August 22, 2004 Pennsylvania Convention Center -- Ballroom B, Oral
Division of Organic Chemistry |