Supramolecular Anisotropy in a Surface-Confined Bicomponent System

Anisotropical engineering of surface-confined supramolecules provides a potential approach to precisely tweaking the properties and performance of low-dimensional molecular nanomaterials. Here, we report the construction of a surface-confined bicomponent supramolecular structure that features structural anisotropy by combined scanning tunneling microscopy and density functional theory studies. One-dimensional supramolecular ribbons formed by corannulene with either titanyl phthalocyanine or copper phthalocyanine exclusively extend along the equivalent <1<(1)over bar>0> directions on Ag(111). Such a supramolecular anisotropy is demonstrated as a result of the combined effects of molecule-substrate commensurability and intermolecular interaction relaxation, which leads to orientation-dependent energy cost for commensurate growth of the supramolecular ribbon on Ag(111). These findings provide insights into the mediation effect of the fine balance between the molecule-substrate and intermolecular interactions on the supramolecular structures, offering an efficient methodology for supramolecular anisotropical engineering.