Poly[di-μ-aqua-μ(4)-(pyrazine-2,5-dicarboxyl-ato)-dilithium(I)].

In the title coordination polymer, Li(2)(C(6)H(2)N(2)O(2))(H(2)O)(2) the pyrazine-2,5-dicarboxyl-ate dianionic ligand bridges two symmetry-independent Li(+) ions using both its N,O-chelating sites. The carboxyl-ate O atom of one of them also bridges to another Li(+) ion, while the second O atom of this group is bonded to another Li(+) ion. Two symmetry-independent water O atoms participate also in the bridging system, which gives rise to a polymeric three-dimensional framework. Both Li(+) ions show distorted trigonal-bipyramidal LiNO(4) coordination geometries, with the N atom in an axial site in both cases. The packing is consolidated by O-H⋯O hydrogen bonds, which occur between water mol-ecules as donors and carboxyl-ate O atoms as acceptors.