A supermolecular building approach for the design and construction of metal-organic frameworks

In this review, we describe two recently implemented conceptual approaches facilitating the design and deliberate construction of metal-organic frameworks (MOFs), namely supermolecular building block (SBB) and supermolecular building layer (SBL) approaches. Our main objective is to offer an appropriate means to assist/aid chemists and material designers alike to rationally construct desired functional MOF materials, made-to-order MOFs. We introduce the concept of net-coded building units (net-cBUs), where precise embedded geometrical information codes uniquely and matchlessly a selected net, as a compelling route for the rational design of MOFs. This concept is based on employing pre-selected 0-periodic metal-organic polyhedra or 2-periodic metal organic layers, SBBs or SBLs respectively, as a pathway to access the requisite net-cBUs. In this review, inspired by our success with the original rht-MOF, we extrapolated our strategy to other known MOFs via their deconstruction into more elaborate building units (namely polyhedra or layers) to (i) elucidate the unique relationship between edge-transitive polyhedra or layers and minimal edge-transitive 3-periodic nets, and (ii) illustrate the potential of the SBB and SBL approaches as a rational pathway for the design and construction of 3-periodic MOFs. Using this design strategy, we have also identified several new hypothetical MOFs which are synthetically targetable.