catena-Poly[[(6-carb­oxy­pyrazine-2-carboxyl­ato)lithium]-μ-aqua]

The asymmetric unit of the title compound, [Li(C(6)H(3)N(2)O(4))(H(2)O)](n), contains an Li(I) ion with a distorted trigonal–bipyramidal coordination environment. It is chelated by a singly protonated ligand mol­ecule via its heterocyclic N atom, by two O aoms, each donated by an adjacent carboxyl­ate group, and is further coordinated by a water O atom which acts as a bridge, forming a mol­ecular ribbon. A proton attached to one of the carboxyl­ate O atoms is situated on an inversion centre and forms a short centrosymmetric hydrogen bond, generating mol­ecular layers parallel to the ac plane. These layers are held together by weak O—H⋯O hydrogen bonds in which the coordinated water mol­ecules act as donors, whereas carboxyl­ate O atoms are acceptors.