Crystal structure of poly[[hexaqua-1κ4O,2κ2O-bis(μ3-pyridine-2,4-dicarboxylato-1κO2:2κ2N,O2′;1′κO4)cobalt(II)strontium(II)] dihydrate]

Abstract

In the title polymeric complex, {[CoSr(C7H3NO4)2(H2O)6]·2H2O}n, the CoIIion, which is situated on a crystallographic centre of inversion, is six-coordinated by two O atoms and two N atoms from two pyridine-2,4-dicarboxylate (pydc2−) ligands and two terminal water molecules in a slightly distorted octahedral geometry, to form atrans-[Co(pydc)2(H2O)2]2−unit. The SrIIion, situated on aC2axis, is coordinated by four O atoms from four pydc2−ligands and four water molecules. The coordination geometry of the SrIIatom can be best described as a distorted dodecahedron. Each SrIIion bridges four [Co(pydc)2(H2O)2]2−units by four COO−groups of four pydc2−ligands to form a three-dimensional network structure. Two additional solvent water molecules are observed in the crystal structure and are connected to the three-dimensional coordination polymer by O—H...O hydrogen bonds. Further intra- and intermolecular O—H...O hydrogen bonds consolidate the overall structure.