Two new architectures based on Anderson-type polyoxoanions and cadmium fragments

Two new hybrid compounds with cadmium cations/coordination complexes as linkers, (C6H5NO2)4[(H2O)14Cd3(CrMo6H6O24)2] 1 (C6H5NO2 = pyridine-4-carboxylic acid) and H[(H2O)2(C6H5NO2)(C6H4NO2)Cd]2[CrMo6H6O24]·9H2O 2 (C6H5NO2, C6H4NO2 = pyridine-3-carboxylic acid), have been synthesized and characterized by elemental analyses, IR, TG, and single-crystal X-ray diffraction. Compound 1 crystallizes in the polar space group Pc and is made up of [CrMo6H6O24]3− polyoxoanions covalently linked by cadmium cations to yield an unprecedented one-dimensional chain, which represents the first example of one-dimensional assemblies based on Anderson-type POMs and cadmium cations. Adjacent inorganic chains are further in close contact by pyridine-4-carboxylic acid glues to form three-dimensional supramolecular polar networks via strong hydrogen-bonding interactions. Compound 2 exhibits a three-dimensional supramolecular channel framework constructed from cationic cadmium-pyridine-3-carboxylic acid coordination polymer sheets pillared by Anderson-type polyoxoanions, with dissociated water molecules situated in the channels. Furthermore, both of the compounds exhibit photoluminescent properties at ambient temperature.