Poly[tetra­aqua­bis­(μ₄-thio­phene-2,5-dicarboxyl­ato)(μ₂-thio­phene-2,5-dicarboxyl­ato)dieuropium(III)]

The three-dimensional coordination polymer, [Eu₂(C₆H₂O₄S)₃(H₂O)₄]_n, has been synthesized under hydro­thermal conditions. The asymmetric unit comprises one Eu³⁺ cation, two aqua ligands and one and a half thiophene-2,5-dicarboxylate anions (the half-anion being completed by a twofold rotation axis). The Eu³⁺ cation is eight-coordinated in a distorted dodeca­hedral geometry. The crystal structure features O—H...O hydrogen bonds.