| Abstract: | The crystal structure of cobalt vanadophosphate dihydrate {systematic name: polydiaqua‐μ‐oxido‐μ‐phosphato‐hemicobalt(II)vanadium(II)]}, Co0.50VOPO4·2H2O, shows a three‐dimensional framework assembled from VO5 square pyramids, PO4 tetrahedra and CoO2(H2O)4] octahedra. The CoII ions have local 4/m symmetry, with the equatorial water molecules in the mirror plane, while the V and apical O atom of the vanadyl group are located on the fourfold rotation axis and the P atoms reside on sites. The PO4 tetrahedra connect the VO5 polyhedra to form a planar P–V–O layer. The Co(H2O)4]2+ cations link adjacent P–V–O layers via vanadyl O atoms to generate an unprecedented three‐dimensional open framework. Powder diffraction measurements reveal that the framework collapses on removal of the water molecules. |
