Towards Complex Matter: Supramolecular Chemistry and Self-organization

Chemistry has developed from molecular chemistry, mastering the combination and recombination of atoms into increasingly complex molecules, to supramolecular chemistry, harnessing intermolecular forces for the generation of informed supramolecular systems and processes through the implementation of molecular information carried by electromagnetic interactions. Supramolecular chemistry is actively exploring systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined functional supramolecular architectures by self-assembly from their components, on the basis of the molecular information stored in the covalent framework of the components and read out at the supramolecular level through specific molecular recognition interactional algorithms, thus behaving as programmed chemical systems. Supramolecular entities as well as molecules containing reversible bonds are able to undergo a continuous change in constitution by reorganization and exchange of building blocks. This capability defines a Constitutional Dynamic Chemistry (CDC) on both the molecular and supramolecular levels. CDC introduces a paradigm shift with respect to constitutionally static chemistry. It takes advantage of dynamic constitutional diversity to allow variation and selection and thus adaptation. The merging of the features of supramolecular systems – information and programmability; dynamics and reversibility; constitution and structural diversity – points towards the emergence of adaptive chemistry. A further development will concern the inclusion of the arrow of time, i.e. of non-equilibrium, irreversible processes and the exploration of the frontiers of chemical evolution towards the establishment of evolutive chemistry, where the features acquired by adaptation are conserved and transmitted. In combination with the corresponding fields of physics and biology, chemistry thus plays a major role in the progressive elaboration of a science of informed, organized, evolutive matter, a science of complex matter.