Acta Cryst. (2009). E65, m352-m353  [ doi:10.1107/S1600536809006515 ]

Bis(6'-carboxy-2,2'-bipyridine-6-carboxylato-³N,N',O⁶)nickel(II) tetrahydrate

H. Wang, H. Su, J. Xu, F. Bai and Y. Gao

Abstract: In the title compound, [Ni(C₁₂H₇N₂O₄)₂]·4H₂O, the Ni atom is located at the centre of a distorted octahedron, formed by four N atoms and two O atoms from the same two tridentating chelated 6-carboxy-2,2'-bipyridine-6'-carboxylate (L) ligands. Face-to-face -stacking interactions between inversion-related pyridine rings with centroid-centroid distances of 3.548 (3) and 3.662 (3) Å (perpendicular distances between the respective rings are 3.314 and 3.438 Å) are found. Intermolecular O-HO hydrogen bonds between water molecules and L ligands form R₅³(10), R₆⁵(14) and R₅⁵(12) rings and also a centrosymmetric cage-like unit of water molecules, which link eight adjacent Ni^II centers, forming a three-dimensional framework.

Online 28 February 2009

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