Crystal Engineering of Hybrid Coordination Networks: From Form to Function

Crystal engineering, the field of chemistry that studies the design, properties, and applications of crystals, is exemplified by the emergence of coordination networks (CNs). CNs are comprised of metal cations or metal clusters linked into 2D or 3D networks by organic and/or inorganic ligands. Early studies on CNs tended to focus upon design using self-assembly and/or reticular chemistry, but interest in CNs has grown exponentially as a consequence of their potential utility in catalysis, purification, sensing, and gas storage. Whereas the use of organic 'linker ligands' has afforded >75 000 metal-organic frameworks (MOFs), hybrid CNs (HCNs) sustained by both inorganic and organic linkers remain understudied. We herein review design approaches to HCNs and recent developments concerning their exceptional gas-separation performance.