Studies on formation and ionic photodissociation of charge-transfer complexes in micelles with electron donor groups. 1. Cationic surfactants with para-substituted benzene rings

Abstract

Ammonium amphiphiles with para-substituted benzene rings at three different positions in the molecular structure were synthesized. Aqueous micellar solutions were obtained with these amphiphiles, and the cmc value decreased as the benzene ring was shifted to the position closer to the polar head group. Charge-transfer complex formation between chloranil or 1,2,4,5-tetracyanobenzene (TCNB) and benzene rings aligned in these micelles was observed. The excitation of charge-transfer bands of TCNB complexes yielded broad structureless fluorescence spectra. Photoinduced charge separation from excited states of TCNB complexes was observed by flash photolysis. The ionic photodissociation of TCNB complexes was strongly affected by the location of the benzene rings in these micellar systems.