Poly[[tetraaquadi-μ4-succinato-μ5-succinato-diytterbium(III)] hexahydrate]

The title compound, {[Yb2(C4H4O4)3(H2O)4]·6H2O}n, is a two-dimensional open-framework built up from centrosymmetric binuclear units developed along [100] through the spacers of four extended ligands, and inter­connected along [101] by two twisted ligands, forming a layered coordination polymer in the (010) plane embedding six uncoordinated water mol­ecules. The water-coordinated YbIII atom completes a nine-coordination mode via seven O atoms from four carboxyl­ate ligands, in a monocapped square anti­prism. One independent succinate ligand, located on an inversion center, is in a bidentate coordination mode, exhibiting an anti conformation. The second independent succinate ligand, in a gauche conformation, is bidentate and bridging–chelating, involving one triply ligating O atom displaying the longest Yb—O bond [2.598 (2) A]. In addition to inter­layer hydrogen bonds, intra­layer hydrogen bonds involve, as acceptors, carboxyl­ate O atoms which are in bidentate mode.