Concerning the supramolecular packing, the solid-state (3D) structure of CPPs has been characterized in several works by means of X-ray diffraction. The molecules self-assemble in a herringbone pattern independently of their size, as it often happens for other π-conjugated systems. An exception is the [6]CPP case, for which three different polymorphs have been found up to date. The first solid-state characterization of [6]CPP revealed a tubular-like structure, but a recent study revealed that the crystallographic structure might depend on the crystalization conditions, finding also a herringbone configuration a few of kcal/mol more stable than the tubular one. More recently, another polymorph of [6]CPP has been found when the crystallization is carried out by sublimation at 220°C. In these conditions, no solvent molecules are occluded inside the [6]CPP cavity, and thus, a concave-convex structure appears (i.e. molecules tightly packed in a T-like shape minimizing the internal space inside the cavities). These findings clearly reveal the subtle yet dominant effect of the weak intermolecular interactions driving the supramolecular self-assembly of these systems.