Influence of Intermolecular N-H•••π Interactions on Molecular Packing and Field-Effect Performance of Organic Semiconductors

Charge transport in organic semiconductors is strongly dependent on their molecular packing modes in the solid state. Therefore, understanding the relationship between molecular packing and charge transport is imperative both experimentally and theoretically. However, so far, the fundamental effects of solid-state packing and molecular interactions (e.g. N-H center dot center dot center dot pi) on charge transport need further elucidation. Herein, indolo[3,2-b]carbazole (ICZ) and a derivative thereof are used as examples to approach this scientific target. An interesting insight obtained thereby is that N-H center dot center dot center dot pi interactions among ICZ molecules facilitate charge transport for higher mobility. Subtle changes in the of N-H center dot center dot center dot pi interactions can significantly influence both the molecular packing and the charge-transport properties. Therefore, a method for exploiting intermolecular N-H center dot center dot center dot pi interactions would yield novel molecular systems with designable characteristics.