Open framework complex constructed from polyoxometalate and dinuclear Cu–phenanthroline

An inorganic–organic hybrid complex, {[Cu2(phen)2(OH)2(H2O)]2[α-SiW12O40]}·8H2O 1, (phen = 1,10-phenanthroline), has been synthesized under mild reaction conditions and characterized by single-crystal X-ray diffraction, IR spectrum, thermal analyses (TG-DTA) and fluorescent measurement. The crystallographic analysis reveals that in the compound, the Keggin polyanion [α-SiW12O40]4− acts as the inorganic building block, two [Cu2(phen)2(OH)2(H2O)] units covalently bond to it via terminal oxygen atoms of the Keggin anion. An open framework is formed through supramolecular interactions with solvent accessible volume of 18% in the unit-cell. Dehydration and re-adsorption of water in 1 were investigated by X-ray powder diffraction (XRPD).The compound shows thermal stability and photoluminescence property in the solid state.