A novel three‐dimensional CdII metal–organic framework based on [Cd6(malonate)6] metallomacrocycles with zeolite SOD (sodalite) topology: poly[ammine‐μ3‐malonato‐cadmium(II)]

A novel Cd^II metal–organic framework, Cd(C₃H₂O₄)(NH₃)]_n, was synthesized by liquid diffusion conducted in the presence of ammonia. The Cd^II atom has seven‐coordinate O₆N pentagonal–bipyramidal geometry. Six Cd^II centers are joined by six malonate ligands to form an S₆‐symmetric Cd₆(malonate)₆] metallomacrocycle, which is further extended through a side‐on chelating malonate ligand to form a three‐dimensional network. Topologically, each Cd^II center is connected to four others to yield an infinite three‐periodic four‐coordinated SOD (sodalite) network with point symbol {4²·6⁴}. The overall network structure in the crystal is maintained and stabilized by the presence of N—H...O hydrogen bonds.