catena-Poly[sodium [[tris(3-methyl-pyridine-2-carboxylato)europate(III)]-μ-3-methylpyridine-2-carboxylato] trihydrate].

In the title structure, {Na[Eu(C(7)H(6)NO(2))(4)]·3H(2)O}(n), the Eu(III) atom is nine-coordin-ated within a slightly distorted tricapped trigonal-prismatic coordination geometry defined by five carboxyl-ate-O atoms and four pyridine-N atoms. One of the carboxyl-ate ligands bridges the Eu cations, forming a one-dimensional coordination polymer along the b axis. The Eu-O bond distances lie within the range 2.362†(4)-2.461†(4)†à . In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link the polymers into a three-dimensional network.