Bis(μ-1<i>H</i>-benzimidazole-5,6-dicarboxylato)bis[tetraaquadicobalt(II)] pentahydrate

Abstract

The title compound, [Co 2 (C 9 H 4 N 2 O 4 ) 2 (H 2 O) 8 ]·5H 2 O, contains two Co II ions that are bridged by two 1 H -benzimidazole-5,6-dicarboxylate ligands to form an M 2 L 2 type complex ( M = metal and L = ligand). There are two crystallographically distinct M 2 L 2 units, each on an inversion centre, along with coordinated and uncoordinated water molecules, in the asymmetric unit. The Co II ions are octahedral. Extensive hydrogen bonding exists between the complex and water molecules, and this helps to stabilize the crystal structure. One water molecule is disordered over two sites with occupancies 0.84:0.16.