Gregor Jung: Approaches to Single-Molecule Chemistry by Means of Fluorescence
|Wanneer:||vr 09-10-2015 09:00 - 10:00|
Although chemists are used to think in terms of individual molecules, i.e. all text book example are depicted as conversion of single molecules, experiments are done with fractions of a mole. Recently, experiments in heterogeneous catalysis showed up where fluorogenic substrates were used to map individual active spots on surfaces.
In the past, we developed fluorescent dyes for studying oxidation reactions and, more recently, for metal-organic catalysis on the single-molecule level. The concept relies on photostable dyes which undergo changes of their fluorescence color during the reaction, and was exemplified in the epoxidation of a double-bond. Multiple fluorescence trajectories allow for reconstructing the potential energy landscape. Whereas suchlike molecules can react only once, the influence of heterogeneous surrounding on chemical reactions can be unraveled by reversible reactions. So-called photoacids, which exhibit proton transfer in the excited state and reprotonation in the ground state, are promising candidates. More opportunities of these dual-emissive probes will be discussed.