Synthesis and Characterization of a Purely Inorganic Open-framework Bimetallic Phosphite with Intersecting 12- and 16-membered Ring Channels

A new three‐dimensional open‐framework cobalt‐zinc phosphite [Co(H2O)4Zn(HPO3)2]·H2O (1), has been prepared under hydrothermal conditions and characterized by single‐crystal X‐ray diffraction, XRD, IR and SQUID magnetometer. The compound crystallizes in the triclinic space group $P{\bar 1}$ with a = 7.552(5), b = 7.671(5), c = 9.443(5) Å, α = 88.538(5)°, β = 89.109(5)°, γ = 87.056(5)°, V = 546.1(6) Å3, Z = 2. The structure of 1 consists of corner‐shared (cs) four‐membered‐ring chains formed by alternating ZnO4 tetrahedra and HPO3 pseudopyramids, which are further linked through CoO2(H2O)4 octahedra giving rise to a three‐dimensional (3‐D) neutral open‐framework with intersecting 12‐ and 16‐MR channels. The synthesis of system required the presence of L‐histidine which is not incorporated into the structure of the product. It is noteworthy that compound 1 represents the only known example of purely inorganic open‐framework cobalt‐zinc phosphite.