Photophysical properties of exciplexes in reverse micelles prepared with benzylhexadecyldimethylammoniun chloride (BHDC)

C. D. BORSARELLI; C.M. PREVITALI

Recent Research Developments in Photochemistry and Photobiology

Transworld Research Network

Lugar: Trivandrum, India.; Año: 2000; p. 197 - 211

The photophysical properties of exciplexes formed between pyrene derivatives with N,N’-dimethylaniline and between 3-methyl indole with benzene were studied in reverse micelles made with the cationic surfactant benzylhexadecyl-dimethylammonium chloride (BHDC) dispersed in benzene. In all cases, the fluorescence of the exciplexes is efficiently quenched either by the surfactant molecules or by the reverse micelle aggregates. The fluorescence properties of the 3 methylindole-benzene exciplex is dependent upon the amount of water dispersed in the microemulsion. Laser flash photolysis experiments for the pyrene-N,N’-dimethylaniline system showed the formation of radical ions, with quantum yields dependent on the composition of the microheterogeneous solution. The results are discussed in terms of the properties of the micellar interface, the partition of the solutes, and the fast exchange of material produced by collisions between reverse micelles.