Poly[triaqua­tris­(μ(4)-pyridine-3,5-dicarboxyl­ato)dicerium(III)]

The asymmetric unit of the title compound, [Ce(2)(C(7)H(3)NO(4))(3)(H(2)O)(3)](n), contains two Ce(III) cations, three pyridine-3,5-dicarboxyl­ate (pyd) anions and three coordinated water mol­ecules. One Ce(III) cation is coordinated by seven carboxyl­ate O atoms from six pyd anions and two water mol­ecules in a square-face-capped square-anti­prismatic geometry. Another Ce(III) cation is coordinated by seven O atoms from six pdy anions and one water mol­ecule in a bicapped trigonal–prismatic geometry. The pdy anions bridge the Ce(III) cations, forming the three-dimensional polymeric structure. The crystal structure contains extensive O—H⋯O, O—H⋯N and weak C—H⋯O hydrogen bonds. π–π stacking is present in the crystal structure, the shortest centroid–centroid distance between parallel pyridine rings being 3.509 (4) Å.