Discovery and introduction of a (3,18)-connected net as an ideal blueprint for the design of metal–organic frameworks

Metal–organic frameworks (MOFs) are a promising class of porous materials because it is possible to mutually control their porous structure, composition and functionality. However, it is still a challenge to predict the network topology of such framework materials prior to their synthesis. Here we use a new rare earth (RE) nonanuclear carboxylate-based cluster as an 18-connected molecular building block to form a gea -MOF ( gea -MOF-1) based on a (3,18)-connected net. We then utilized this gea net as a blueprint to design and assemble another MOF ( gea -MOF-2). In gea -MOF-2, the 18-connected RE clusters are replaced by metal–organic polyhedra, peripherally functionalized so as to have the same connectivity as the RE clusters. These metal–organic polyhedra act as supermolecular building blocks when they form gea -MOF-2. The discovery of a (3,18)-connected MOF followed by deliberate transposition of its topology to a predesigned second MOF with a different chemical system validates the prospective rational design of MOFs. It is often difficult to predict or control the topologies of metal–organic frameworks (MOFs) before synthesis. Now, the topology of a MOF has been used as an ideal blueprint for the deliberate design of a related MOF, by substitution of molecular building blocks with supermolecular building blocks. The two MOFs share the same underlying topology but have different chemical compositions.