Tailored solution-based N-heterotriangulene thin films: Unravelling the self-assembly.

The ability of a series of bridged triarylamines, so-called N -heterotriangulenes, to form multilayer-type 2D-extended films via a solution-based processing method was examined using complementary microscopic techniques. We found that the long-range order, crystallinity and layer thickness decisively depend on the nature of the substituents attached to the polycyclic backbone. Owing to their flat core unit, compounds exhibiting a carbonyl unit at the bridge position provide a superior building block as compared to thioketo-bridged derivatives. In addition, nature and length of the peripheral substituents affect the orientation of the aromatic core unit within highly crystalline films. Hence, our results stress the significance of a suitable molecular framework and provide deeper understanding of structure formation in 2D-confined surroundings for such compounds.