THE ACCUMULATION OF PHOTOCHROMIC ENERGY ACCEPTOR SPECIES IN A-S DYAD LANGMUIR-BLODGETT-FILMS

Fluorescence and absorption spectra were measured on Langmuir-Blodgett (LB) films containing acceptor-sensitizer (A-S) dyads. In the dyads, the length of hydrocarbon bridges interconnecting acceptor (viologen) and sensitizer (pyrene) were synthetically changed. In the LB films, t he accumulation of viologen cation radical which can quench the excite d pyrene moiety as an energy acceptor was observed during UV irradiati on under N-2. The rate constant of photoinduced intramolecular electro n transfer in the LB films was estimated from the fluorescence intensi ties by taking the energy transfer quenching into consideration. (C) 1 998 Elsevier Science S.A, All rights reserved.