Substrates for Irreversible Reactions

Irreversibility is not meant in a purely thermodynamic sense but more from a kinetic understanding we denote reactions as irreversible when the backreaction is unlikely to occur within the time frame of observation. Those transformations impose several obstacles to their implementation in single-molecule research. Under practical considerations, only reactions in which their onset is triggered by the excitation Ught are susceptible to continuous single-molecule observation by the widely used photon-counting point detectors. All other reactions demand 

Another challenge is the conversion number within the observation volume of 1 fl. Assuming an elementary bimolecular reaction where both molecules are fluorescing, their concentration should not exceed 1 nM. Even if diffusion-controlled conditions are assumed, that is, 10 s , only one reactive collision 

Approaching Single-Molecule Studies in Homogeneous Catalysis 

A main idea of this project was the observation of immobilized metal complexes and their catalytic activity at the single-molecule level with the aid of fluorophores 

A catalytic reaction involves several molecular interactions between the catalyst and the reactant. In order to study these complex interactions, we first need precise knowledge of the dynamics in the ligand sphere of transition metals. We used model compound 2a that translates the complexation dynamics of a Cu(II)-bipyridine complex into changes of the fluorescence emitted by 

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