DEACTIVATION OF EXCITED SPECIES BY DIFFUSION-CONTROLLED QUENCHING IN CLUSTERS OF REVERSED MICELLES

Kinetic models for the deactivation of excited species by quenching in clusters of micelles are presented and tested experimentally by measurement of phosphorescence deactivation in clusters of AOT-water reversed micelles having an H2O/AOT molar ratio of 12.5 in dodecane. Models were devised for a random walk of quenchers in compact clusters, in open and ramified clusters (fractal clusters), and also a model especially adapted for very small clusters. Experimental studies under these conditions gave consistent results for the walk frequency, k(w), for which a value of (2-4) X 10(5) s-1 was obtained. Similar values were obtained with several different probe-quencher pairs, which supports the proposed fusion-fission mechanism for the transport between the micelles. The rate constant k(w) reflects the rate of fusion of the micelles.