First examples of room-temperature discotic nematic liquid crystals exhibiting ambipolar charge carrier mobilities

Abstract

Four new room-temperature nematic liquid-crystalline (LC) dimers consisting of a wedge-shaped 3,4,5-tridecyloxy gallic ester molecule linked to either cyanobiphenyl, cholesteryl, pentaalkynylbenzene or triphenylene based moieties are reported. Dimers with pentaalkynylbenzene and triphenylene moieties in their room-temperature discotic nematic (N_D) mesophase show ambipolar charge carrier mobilities of the order of 10⁻⁵ cm² V⁻¹ s⁻¹ and 10⁻³ cm² V⁻¹ s⁻¹, respectively, as measured using a time-of-flight (ToF) technique.