The purpose of the present work is to delineate similarities as well as differences concerning the charge transporting properties of π-conjugated polymers as well as of discotic liquid crystals. Materials investigated are a (i) ladder-type poly-paraphenylene (LPPP), (ii) a member of the phenylenevinylene family, and (iii) several asymmetrically substituted triphenylenes. The disorder formalism explains the field and temperature dependence of the mobility adequately provided that the disorder, which is controlled by the sample topology and random dipolar electric fields, is sufficiently large. Differences are noted in highly ordered LPPP and in symmetric discotic crystals. It is conjectured that finite size effects in the case of LPPP and dynamic effects in the liquid crystals overcompensate the effect of energetic disorder.
D. Hertel, A. Ochse, V. I. Arkhipov, H. Bässler, "Recent Advances in Charge Transport in Random Organic Solids: The Case of Conjugated Polymers and Discotic Liquid Crystals" in Journal of Imaging Science and Technology, 1999, pp 220 - 227, https://doi.org/10.2352/J.ImagingSci.Technol.1999.43.3.art00005