Poly[μ-aqua-diaqua­(μ(2)-pyrazine-2,3-dicarboxyl­ato)dilithium(I)]

The asymmetric unit of the title compound, [Li(2)(C(6)H(2)N(2)O(4))(H(2)O)(3)](n), consists of two independent Li(+) cations, one pyrazine-2,3-dicarboxyl­ate dianion and three water mol­ecules. One of the Li(+) cations has a distorted tetra­hedral geometry, coordinated by one of the carboxyl­ate O atoms of the pyrazine-2,3-dicarboxyl­ate ligand and three O atoms from three water mol­ecules, whereas the other Li(+) cation has a distorted trigonal-bipyramidal geometry, coordinated by a carboxyl­ate O atom of a symmetry-related pyrazine-2,3-dicarboxyl­ate ligand, two water mol­ecules and a chelating pyrazine-2,3-dicarboxyl­ate ligand (by utilizing both N and O atoms) of an adjacent mol­ecule. The synthesis of a hydrated polymeric dinuclear lithium complex formed with two pyrazine-2,3-dicarboxylic acid ligands has been reported previously [Tombul et al. (2008a ▶). Acta Cryst. E64, m491–m492]. By comparision to the complex reported here, the dinuclear complex formed with two pyrazine-2,3-dicarboxylic acid ligands differs in the coordination geometry of both Li atoms. The crystal structure further features O—H⋯O and O—H⋯N hydrogen-bonding inter­actions involving the water mol­ecules and carboxyl­ate O atoms.