Enhanced SHG in polyelectrolyte complexed hemicyanine dye Langmuir-Blodgett films

Abstract

Complexation of ionic amphiphiles at the air-water interface by polyelectrolytes in the subphase has a pronounced effect of stabilization and deaggregation on the amphiphiles. We have effectively utilized the latter in the case of a hemicyanine dye based amphiphile. The aggregation of these amphiphiles is influenced by the rate of equilibration of the Langmuir film and the introduction of polyelectrolytes in the subphase is found to be a convenient method to suppress the aggregation. Langmuir-Blodgett films obtained by transfer of the polyelectrolyte complexed amphiphiles show enhanced second harmonic generation.