Three novel heterobimetallic Cd/Zn-Na coordination polymers: Syntheses, crystal structure, and luminescence

Three novel heterobimetallic coordination polymers, {Na-2[Cd(odpa)(H2O)]}(n) (1), [Na-2[Zn(odpa)(H2O)]}(n) (2), and {Na-2[Cd-3(odpa)(2)(H2O)(5)]center dot 1.5H(2)O}(n) (3) (H4odpa = 4,4'-oxydiphthalic acid), have been prepared under solvothermal conditions and characterized by single-crystal X-ray diffraction. Compounds 1 and 2 are unprecedented 2D bilayer anion networks containing 26and 24- membered channels made of Cd/Zn polyhedra linked by (odpa)4- ligand, while a novel 2D Na-O network is inserted subtly in the bilayer networks. Compound 3 presents a three-dimensional coordination polymer based on both tetranuclear and hexanuclear heterobimetallic clusters containing one-dimensional hydrophilic channels, where guest water molecules reside. Furthermore, these heterobi metallic clusters connected to each other to build a Cd-Na polyhedral network existing in a 3D anion framework. Compounds 1-3 are all heterobimetallic Cd/Zn-Na compounds containing polymeric anions, which have not been reported in all coordination polymers of (odpa)(4-) ligand. In 1-3, central Cd-II/Zn-II ions and (odpa)(4-) figand display completely different coordination modes and conformations. In addition, the thermal stabilities and photoluminescence properties were also studied.