Structure–Property Correlation behind the High Mobility of Carbazolocarbazole

A comparative study of carbazolocarbazole isomers and their respective N-alkyl derivatives confirms the good performance of carbazolo­[2,1-a]­carbazole as hole-transporting material in organic field effect transistors. The azaphenacene structure of this molecule forms a dense packing promoted by particularly short longitudinal shifts between molecules establishing face-to-face and edge-to-face interactions. Computational calculations have determined an almost isotropic 2D transport environment within a lamellar structure. This favorable solid state arrangement, in combination with appropriate interfacial layers, has led to a high mobility (1.3 cm2 V–1 s–1) that validates the aptitude of this molecular material as an organic semiconductor.