The leading role of the steric hindrance effect and dipole-dipole interaction in superlattice nanostructures formed via the assembly of discotic liquid crystalsElectronic supplementary information (ESI) available. See DOI: 10.1039/c8nj05405c

To reveal the relationships among molecular structures, self-assembly behavior and the organic electronic properties of discotic liquid crystals, 2-(neopentyloxy)-3,6,7,10,11-pentakis(pentyloxy)triphenylene (T5ON1) and 2-pivalate-3,6,7,10,11-penta-pentyloxy-triphenylene (T5EP1) have been synthesized based on hexapentyloxy-triphenylene (HAT5). Their mesomorphic properties were studied by differential scanning calorimetry (DSC), one-dimensional wide-angle X-ray diffraction (1D WAXD) and two-dimensional wide-angle X-ray diffraction (2D WAXD). T5ON1 and T5EP1 showed an ordered hexagonal columnar phase and a highly ordered hexagonal columnar plastic phase, respectively. To our surprise, Transmission Electron Microscope (TEM) images proved that a uniformly distributed superlattice nanostructure formed in the organic system of T5EP1. In addition, the hole and electron mobilities of T5EP1, which were 3.66 × 10 −2 cm 2 V −1 s −1 and 3.33 × 10 −2 cm 2 V −1 s −1 , respectively, indicated that T5EP1 was a bipolar charge carrier transport material. The effect of steric hindrance and dipole-dipole interactions are a prerequisite for the formation of ordered plastic phases.