Crystal structure of catena-poly[[di-aqua-di-imida-zole-cobalt(II)]-μ2-2,3,5,6-tetra-bromo-benzene-1,4-di-carboxyl-ato].

The asymmetric unit of the title compound, [Co(C8Br4O4)(C3H4N2)2(H2O)2] n or [Co(Br4bdc)(im)2(H2O)2] n , comprises half of CoII ion, tetra-bromo-benzene-dicarboxylate (Br4bdc2-), imidazole (im) and a water mol-ecule. The CoII ion exhibits a six-coordinated octa-hedral geometry with two oxygen atoms of the Br4bdc2- ligand, two oxygen atoms of the water mol-ecules, and two nitro-gen atoms of the im ligands. The carboxyl-ate group is nearly perpendicular to the benzene ring and shows monodentate coordination to the CoII ion. The CoII ions are bridged by the Br4bdc2- ligand, forming a one-dimensional chain. The carboxyl-ate group acts as an inter-molecular hydrogen-bond acceptor toward the im ligand and a coordinated water mol-ecule. The chains are connected by inter-chain N-H⋯O(carboxyl-ate) and O-H(water)⋯O(carboxyl-ate) hydrogen-bonding inter-actions and are not arranged in parallel but cross each other via inter-chain hydrogen bonding and π-π inter-actions, yielding a three-dimensional network.