Poly[di-μ(2)-aqua-μ(2)-(5-methyl-pyrazine-2-carboxyl-ato)-(5-methyl-pyrazine-2-carboxyl-ato)-μ(3)-nitrato-trilithium].

The asymmetric unit of the title compound, [Li(3)(C(6)H(5)N(2)O(2))(2)(NO(3))(H(2)O)(2)](n) contains three Li(I) ions, two ligand anions, two water mol-ecules and a nitrate anion. Related by a centre of inversion, they form a centrosymmetric mol-ecular cluster in which one of the Li(I) ions shows trigonal-bipyramidal and the other two distorted tetra-hedral coordination. Li(I) ions are bridged by water O atoms and carboxyl-ate O atoms donated by one of the ligands. The clusters, bridged by two nitrato O atoms, form mol-ecular columns along [010], which are held together by O-H⋯O and O-H⋯N hydrogen bonds and π-π inter-actions [centroid-centroid distances = 3.694†(1) and 3.796†(1)†à ].