catena-Poly[[[penta-aqua-cerium(III)]-µ-pyridine-2,4,6-tricarboxyl-ato-κ(4)N,O(2),O(6):O(6')] tetra-hydrate].

The Ce(III) atom in the title compound, {[Ce(C(8)H(2)NO(6))(H(2)O)(5)]·4H(2)O}(n), is N,O,O'-chelated by the carboxyl-ate trianion and is coordinated by five water mol-ecules; a carboxyl O atom from an adjacent trianion bridges the Ce(III) atom, resulting in a chain running along the a axis. The nine atoms surrounding the metal atom comprise a tricapped trigonal-prismatic polyhedron. The coordinated and lattice water mol-ecules inter-act with each other and with the carboxyl O atoms by O-H⋯O hydrogen bonds, generating a three-dimensional network.