Poly[[[diaquabis(pyridine-4-carboxamide-kappa N-1)cobalt(II)]-mu(2)-squarato-kappa O : O '] dihydrate]

Abstract

The title polymeric compound, {[Co(C4O4)(C6H6N2O)(2)-(H2O)(2)].2H(2)O}(n), has two crystallographically independent half-molecules in the asymmetric unit, each Co atom residing on a center of symmetry. The two polymeric chains exhibit similar coordination geometry but display differences with regard to other structural features. Each Co-II center is octahedrally coordinated by two mutually trans pyridine-4-carboxamide ( or isonicotinamide) ligands, two mutually trans squarate ligands and two trans aqua ligands. The crystal structure contains chains of squarate-1,3-bridged Co-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.