Search for conducting doped polymers with great chemical stability: Regiospecific poly(3,3''-dihexyl-2,2':5'3''-terthiophe)

Previous calculations have suggested that the formation and the stability of charge transfer bonds in doped polyconjugated systems may be maximized by a favored topology of the dopant molecule. The preferred site of attack is found where the steric hindrance is minimized. Following these principles, regiospecific poly(3,3 ''-dihexyl-2,2':5',2 ''-terthiophene) was synthesized and doped with FeCl3. The time and temperature dependence of the dedoping process has been studied by the analysis of the doping induced infrared spectrum. This material in the doped state shows an extremely great stability (in air. even at relatively high temperatures) never previously reported for any other doped system.