Liquid crystalline photoconductors

The influence of molecular order as well as of orientation of charge carrier units on photoconductivity has been investigated for the liquid crystal photoconductors H5T (1), thiadiazole (2) and oxadiazole (3). The discotic H5T (1) and both smectic systems 2 and 3 exhibit a higher photocurrent in the highly ordered mesophase than in the polycrystalline or isotropic state. For 1, results concerning charge carrier transport mechanism and Dember effect are given indicating an electronic charge transport comparable with the one known for single crystalline anthracene.