A new family of luminescent lanthanide based coordination polymers

Reaction in water between a lanthanide ion (Ln = Sm–Dy) and the sodium salt of isophthalic acid leads to a new family of lanthanide-based coordination polymers. The crystal structure has been solved on the basis of the Gd containing compound. The iso-structurality of the other compounds has been assumed on the basis of powder X-ray diffraction diagrams. These compounds of general formula Ln2(OH)(C8H4O4)2(C8H5O4)(H2O)8·6H2O crystallize in the monoclinic system, space group P21/a (no. 14) with a = 17.4249(2) Å, b = 10.9148(1) Å, c = 20.7216(2) Å, β = 113.1694(4)° and Z = 4. This crystal structure is 1-D. Chains are bound to each other by hydrogen bonds. The thermal stability of these compounds is described and discussed as well as luminescent properties of the coordination polymers involving luminescent rare earth ions.