Poly[tri-μ-aqua-diaqua-μ-phosphonoformato-cobalt(II)sodium]

Abstract

The title complex, [CoNa(CO5P)(H2O)5]n, was obtained by reacting sodium phosphonoformate with cobalt nitrate. The complex contains cobalt(II) and sodium ions, which are bridged by the O atoms of two aqua ligands. The CoII ion is octahedrally coordinated by three phosphonoformato ligands (one bi- and the other monodentate) and by two O atoms from the bridging aqua ligands. The sodium cation is hexacoordinated by six O atoms from four bridging and two terminal aqua ligands. The complex molecules are linked to give a three-dimensional structure by phosphonoformate ligands bridging CoII atoms and water molecules establishing cobalt–sodium bridges. O—H...O hydrogen bonding between the aqua ligands and all O atoms of the phosphonoformato ligand and neighbouring aqua ligands help to consolidate the packing.