Photochemical reactions, organized assemblies effects

Whiten D.G., Russell J.C., and Schmehl, R.H., Photochemical reactions in organized assemblies environmental effects on reactions occurring in micelles, vesicles, films and multilayer assembles and at interfaces . Tetrahedron, 38, 16,2455-2487. (1982)... 

Section 1 deals with the formal kinetics of the photochemical reactions in micellar solutions and its application to determine the rate constants of photoprocesses, the critical concentration of micellization (CMC) and the aggregation number of micelles from experimental data. In Section 2 the correlations of the rate constants of the photochemical charge separation and mass transfer processes with its thermodynamics, and also the microviscosity and effective polarity of organized assemblies are considered. 

Functionalized polyelectrolytes are promising candidates for photoinduced ET reaction systems. In recent years, much attention has been focused on modifying the photophysical and photochemical processes by use of polyelectrolyte systems, because dramatic effects are often brought about by the interfacial electrostatic potential and/or the existence of microphase structures in such systems [10, 11], A characteristic feature of polymers as reaction media, in general, lies in the potential that they make a wider variety of molecular designs possible than the conventional organized molecular assemblies such as surfactant micelles and vesicles. From a practical point of view, polymer systems have a potential advantage in that polymers per se can form film and may be assembled into a variety of devices and systems with ease. 

Photochemistry in micellar systems is a type of micellar catalysis in the sense that the photochemical process takes place in the micellar domain. The outstanding recent progress in micellar photochemistry is well laid out in a number of review articles and papers on photochemical and photophysical processes in micellar assemblies. " As described in previous chapters, hydrophobic organic solutes solubilize well in the micellar core, whereas the micellar surface controls the concentration of hydrophilic solutes. The electrostatic potential of up to a few hundred millivolts at the surface of ionic micelles is especially effective in attracting or repelling ionic species. Thus, micelles are microscopically heterogeneous and well suited as surfaces for reactions of appropriate reactants. 

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