ABSTRACT The role played by the electrically charged interfaces of various closed organized media has been studied through two types of election transfer reactions : photoionization of chromophores such as perylene or tetramethylbenzidine embedded in the lipidic phase of the aggregates, and intermolecular electron transfer, thermal or photoinduced. These electron transfers occur, either directly from a photoexcited donor to an acceptor, or more generally from various nucleophilic species to the photocation. For these two kinds of reaction, the influence of the electrical interfacial potential and also the structure of the aggregates have been evidenced. Particulary, quantitative relationships between the electrical potential and photoionization yields or photocation decay rate constant have been established in the case of negatively charged interfaces of micelles or vesicles. In such conditions, the ion recombination reaction can be notably reduced which illustrates the potentialities of properly chosen aggregates as compared with homogeneous solutions.
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