ИСТИНА

Commonly organic semiconducting materials are divided by the charge transport type into the so-called n-type and p-type groups . In practice, the type of charge transport in material is not easily switched. Fluorination is a well-known approach to alter the electronic properties of p-conductive semiconductors. For example, common p-conductive organic semiconductors such as pentacene, copper phthalocyanine, diethynyl naphthalene and oligophenylenevinylenes can be converted to the n-conductive ones via fluoro-substituents , . This can be attributed to the change of energy level alignment at the metal/organic interface favoring electron over hole injection. Here, we study the impact of fluorination of the methyl terminal group on the structural and electronic properties of single- and polycrystals of thiophene-phenylene co-oligomers (TPCO) with the phenylene-thiophene-thiophene-phenylene (PTTP) conjugated core using x-ray diffraction, DFT, GW and dipole moment calculations, ultra-violet photoelectron spectroscopy (UPS) and field-effect transistor (FET) measurements.