Adsorbate−Substrate-Mediated Growth of Oligopyridine Monolayers at the Solid/Liquid Interface

Oligopyridine molecules are highly efficient building blocks for the construction of two-dimensional nanopatterns by self-assembly processes at the highly oriented pyrolytic graphite (HOPG)−liquid interface based on intermolecular (weak) hydrogen bonds between the terminal pyridine moieties. By introducing additional phenylene groups the principal hydrogen bonding function is maintained but the adsorbate−substrate interactions are favored over the adsorbate−adsorbate interactions leading to more unified structures and a stronger orientation of the adlayer on the underlying HOPG. Thus, by tailoring the molecules, the self-assembly behavior can be fine-tuned and directed toward the desired pattern. Though the molecules are achiral, chiral polymorphic phases are found caused by asymmetric hydrogen bonding interactions.