Bis(μ-benzene-1,2-dicarboxylato)bis{aqua[2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline]cadmium(II)} and its zinc(II) analogue

In the isomorphous title compounds, [Cd-2(C8H4O4)(2)(C19H10ClFN4)(2)(H2O) 2] and [Zn-2(C8H4O4)(2)(C19H10ClFN4)(2)(H2O)(2)], the Cd-II centre is seven-coordinated by two N atoms from one [2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (L) ligand, one water O atom and four carboxylate O atoms from two different benzene-1,2-dicarboxylate (1,2-bdc) ligands in a distorted pentagonal-bipyramidal coordination, while the Zn-II centre is six-coordinated by two N atoms from one L ligand, one water O atom and three carboxylate O atoms from two different 1,2-bdc ligands in a distorted octahedral coordination. Each pair of adjacent metal centres is bridged by two 1,2-bdc ligands to form a dimeric structure. In the dimer, each L ligand coordinates one metal centre. The dimer is centrosymmetric, with a crystallographic inversion centre midway between the two metal centres. The aromatic interactions lead the dimers to form a two-dimensional supramolecular architecture. Finally, O-H center dot center dot center dot O and N-H center dot center dot center dot O hydrogen bonds reinforce the two-dimensional structures of the two compounds.