Poly[[triaqua-(μ(3)-4-oxidopyridine-2,6-dicarboxyl-ato)terbium(III)] monohydrate].

In the title coordination polymer, {[Tb(C(7)H(2)NO(5))(H(2)O)(3)]·H(2)O}(n), the Tb(III) atom is eight-coordinated by a tridentate 4-oxidopyridine-2,6-dicarboxyl-ate trianion, two adjacent monodentate anions and three water mol-ecules, forming a distorted bicapped trigonal-prismatic TbNO(7) coordination environment. The anions bridge adjacent Tb(III) ions into double chains. Adjacent chains are further connected into sheets parallel to (10). O-H⋯O hydrogen bonds involving both coordinated and uncoordinated water mol-ecules generate a three-dimensional network.