Electric field effects on fluorescence of pyrene in a homogeneously distributed system and in an oriented molecular system

Electric field effects on fluorescence of pyrene deposited in a mixed LB film with a definite direction are very different from those of pyrene doped randomly in a polymer film. In polymer films, both the sharp structured monomer fluorescence emitted from the locally excited state and the sandwich-type excimer fluorescence with a peak at approx. 470 nm are quenched by an electric field, whereas another excimer fluorescence with a peak at approx. 415 nm is enhanced by an electric field. In LB films, the latter excimer fluorescence is not affected by an electric field.