The crystal structure of a new polymorph of hexaaquanickel(II) bis(6-oxo-1,6-dihydropyridine-3-carboxylate)

Abstract

In a new polymorph of the title salt, [Ni(H2O)6](C6H4NO3)2, the metal atom of the cationic complex lies on a symmetry centre and is coordinated by six water molecules to provide a quite regular octahedral coordination environment. These cations interact with 6-oxo-1,6-dihydropyridine-3-carboxylate anions through electrostatic interactions and by means of O—H...O and N—H...O hydrogen bonds involving the carboxylate, keto and protonated imine groups of the anion, and the coordinating water molecules from the cationic complex entity to generate a supramolecular three-dimensional architecture. The previously reported polymorph of this compound presents a network of hydrogen bonds, in which the organic anions establish mutual hydrogen-bonding interactions involving their keto and protonated imine groups.

Keywords

• crystal structure
• polymorph
• 6-oxo-1,6-dihydropyridine-3-carboxylate anion
• hydrogen bonding,