Poly[[triaqua-(μ(3)-pyridine-2,4,6-tri-car-boxyl-ato)gadolinium(III)] monohydrate].

The title compound, {[Gd(C(8)H(2)NO(6))(H(2)O)(3)]·H(2)O}(n), was obtained in water under hydro-thermal conditions. The Gd(III) ions are nine-coordinated by two O and one N atoms from one pyridine-2,4,6-tricarboxyl-ate ligand, two O atoms from another ligand, one O atom from a third ligand and three coordinated water mol-ecules. Each ligand binds three metal centers. Two-dimensional layers are formed through the Gd-O bonds and the layers are linked by O-H⋯O hydrogen bonds, forming a three-dimensional network.