Poly[μ-aqua-aqua-μ-3-carboxypyrazine-2-carboxylato-sodium(I)]

The crystal structure of the title compound, [Na(C6H3N2O4)(H2O)(2)](n), consists of molecular ribbons containing octahedral NaO5N units. Two adjacent Na atoms are bridged by two water molecules to give a centrosymmetric dimeric unit. Each Na centre is coordinated by two carboxylate groups. The ligand also uses one N atom to coordinate to Na. In addition, each Na atom is coordinated by one water O atom, raising the coordination number to six. One of the carboxyl groups retains its H atom, which takes part in an O-H center dot center dot center dot O [O center dot center dot center dot O = 2.563 (1) angstrom] intramolecular hydrogen bond.