(IUCr) Crystallography Journals Online

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Acta Cryst. (2008). E64, m387-m388 [ doi:10.1107/S1600536808001372 ]

Bis(4,4'-bipyridinium) di--hydroxido-bis[dihydroxido(pyridine-2,6-dicarboxylato)antimonate(III,V)] octahydrate

J. Soleimannejad, H. Aghabozorg, Y. M. A. Golenji, J. Attar Gharamaleki and H. Adams

Abstract: The reaction of antimony(III) chloride, 4,4'-bipyridine (4,4'-bipy) and pyridine-2,6-dicarboxylic acid (pydcH₂), in a 1:2:2 molar ratio in an aqueous solution, resulted in the formation of the title centrosymmetric disordered mixed-valence Sb^III/Sb^V compound, (C₁₀H₉N₂)₂[Sb₂(C₇H₃NO₄)₂(OH)₆]·8H₂O or (4,4'-bipyH)₂[Sb(pydc)(OH)₂( [mu] -OH)]₂·8H₂O. The seven donor atoms of the (pydc)^2- groups and the hydroxido ligands form a distorted pentagonal-bipyramidal arrangement around the Sb^III/Sb^V centers. C-H [pi] stacking interactions between CH groups of the complex dianion and the aromatic rings of the (4,4'-bipyH)⁺ cations, with a distance of 2.89 Å, are observed. In the crystal structure, a wide range of noncovalent interactions, consisting of O-HO, N-HO and C-HO hydrogen bonds [DA ranging from 2.722 (2) to 3.137 (3) Å], ion pairing, [pi] - [pi] stacking [centroid-centroid distance of 3.4363 (13) Å] and C-H [pi] interactions, connect the various components into a supramolecular structure.