Photochemical responses of asymmetrically self-organized molecular films prepared on a water surface

Ultrathin polymer films incorporating amphiphilic ruthenium (II) polypyridine complex (Ru2C16B) or viologen (LPV) were prepared by casting a mixed solution on a water surface. Interfacial photoinduced energy-transfer from coumarin dye (CoD) on the glass plate to Ru2C16B in the polymer film indicated asymmetric population of Ru2C16B at a single surface of the film. Phoinduced electron-transfer from Ru2C16B to LPV across the films also verified asymmetric enrichment of these amphiphilic dyes. The results establish a novel and simple method of asymmetric self-organization of amphiphilic dyes in the thin polymer film.