Poly[bis­(N,N-dimethyl­formamide)tris­(μ4-trans-stilbene-4,4′-dicarboxyl­ato)­tricadmium(II)]: a two-dimensional network with an unusual 36 topology

In the title compound, [Cd3(C16H10O4)3(C3H7NO)2]n or [Cd3(SDA)3(DMF)2]n (H2SDA is trans-stilbene-4,4′-dicarboxylic acid and DMF is dimethyl­formamide), the linear dicarboxylate ligand forms a two-dimensionally layered metal–organic network with the relatively uncommon 36 topology. The structure reveals trinuclear secondary building units and has an octa­hedral geometry at a central metal ion (occupying a symmetry site) and tetra­hedral geometries at two surrounding symmetrically equivalent metal ions lying on a threefold axis. The six-connected planar trinuclear CdII centers, Cd3(O2CR)6, play a role as potential nodes in generation of the relatively uncommon 36 topology. The coordinated DMF unit is disordered around the threefold axis

Highly selective separation of small hydrocarbons and carbon dioxide in a metal–organic framework with open copper(ii) coordination sites

Hydrocarbons and carbon dioxide are very important raw materials for industrial products and fine chemicals. The microporous metal-organic framework ZJU-25 with high density of open metal sites, has significantly better separation potential than other MOFs, ZIFs or zeolites. It can fractionate a 5-component CH4/C2H2/C2H4/C2H6/CO2 mixture to yield individual pure components as established by the sorption isotherms and simulated breakthrough and pulse chromatographic experiments. Such separations are likely to have a significant industrial impact, resulting in significant energy savings when compared to current technologies that rely on cryogenic distillation