The design and synthesis of advanced and multifunctional materials relies on a detailed understanding of how the geometric features of chemical subunits govern the structures they form. The (supra)molecular architectures which may arise when combining subunits is constrained by the geometric feasibility of subunits' self-assembly into a given shape class, among other factors. By careful design choices, chemists may synthesise chemical architectures of various shapes. These architectures may also incorporate features which allow for the binding of particular hosts or guests, or dynamic structural reconfiguration in designed supramolecular systems.
Various supramolecular design strategies exploit these principles, including the directional bonding approach,[1] molecular panelling approach[2], and symmetry interaction approach.[3] These have proven to be robust methodologies for synthesising supramolecular solids resembling Platonic, Archimedean and other three-dimensional architectures. However, these approaches bear some inherent limitations when regarding the types of subunits which may be considered. For example, the above approaches pertain to subunits bearing an appropriate orientation of chelate groups, planar face-occupying subunits and rigid subunits.
In this work, geometric principles from the aforementioned supramolecular design philosophies are expanded upon, affording precise predictions of discrete molecular architecture type. This updated methodology is applicable to any pair of rotationally symmetric subunits and assesses all point symmetries which can be accessed by the given combination of rotationally symmetric subunits. Comparative evaluation of various product shapes may be made in order to inform design or structural analysis.
Modelling and preliminary implementations of this methodology are presented, demonstrating its utility in the targeted design of discrete molecular structures bearing structural features for desirable functionalities.