Fluorescence Anisotropy and Decay Times of Pyrene and Pyrene Excimer in Cellulose Acetate Films at Various Temperatures

Abstract Investigations of fluorescence anisotropy and mean lifetime of pyrene and pyrene excimer in cellulose acetate films have shown that this environment can not be considered as a strictly rigid solution, being rather a medium consisting of empty spaces where small pyrene molecules have considerable freedom. It has been concluded that the mechanism of the excimer formation is the same as that in liquid solvents.