Catena-Poly[[[Diaquabis(pyridine-4-carboxamide-κN)copper(II)]-μ(2)-Squarato-κO-1 : O-3] Dihydrate]

Abstract

The asymmetric unit of the title compound, {[Cu(C<inf>4</inf>O <inf>4</inf>)(C<inf>6</inf>-H<inf>6</inf>N<inf>2</inf>O)<inf>2</inf>(H <inf>2</inf>O)<inf>2</inf>]·2H<inf>2</inf>O}<inf>n</inf>, consists of one pyridine-4-carbox-amide (isonicotinamide or ina) ligand, one-half of a squarate dianion, a coordinated aqua ligand and a solvent water molecule. Both the CuII and the squarate ions are located on inversion centers. The CuII ions are octahedrally surrounded by four O atoms of two water molecules and two squarate anions, and by two N atoms of the isonicotinamide ligands. The crystal structure contains chains of squarate-1,3-bridged Cu II ions. These chains are held together by N-H⋯O and O-H⋯O intermolecular hydrogen-bond interactions, forming an extensive three-dimensional network. © 2005 International Union of Crystallography.