Thermal activation behavior of carrier mobility in perfluoroalkylated triphenylene derivatives

Abstract

The mesomorphic thermal stability of perfluoroalkylated triphenylenes is increased in the hexagonal columnar (Col_h) phase in comparison to that the corresponding alkoxytriphenylenes. Nevertheless, the charged carrier mobilities are comparable to the hydrocarbon homologues ( ~10^-4 cm²/Vs), and also the charged carrier mobilities show Arrehenius behavior. However, the regimes with different activation energies are recognized in the temperature range of Col_h phase, despite the phase transition was not observed in this regime with DSC and X-Ray diffraction. In this work, the temperature dependence of FT-IR spectra were measured to discuss on the dynamic aspect of molecules in the Col_h phase.