The radiation-induced coloration of amorphous photochromic dithienylethene films

The radiation-induced coloration of bulk amorphous films of five photochromic diarylethenes was studied with the aim of developing reusable, sensitive color dosimeters. The films contain an extremely high concentration of diarylethenes. The most intense coloration was observed for the film containing 1,2-bis(2,4-dimethyl-3-thienyl)perfluorocyclopentene having 3-phenyl-4-diphenylyl substituents. The color disappeared upon irradiation with visible light. The coloration increased linearly with an increase in the absorbed dose up to 3000 Gy. The relative sensitivity of radiation-induced coloration among the five derivatives qualitatively agreed with the sensitivity of photo-induced coloration from UV light (254 nm) irradiation.