catena-Poly[[(pyrazine-2-carboxamide-κN (4))copper(I)]-μ(3)-iodido]

In the title metal–organic polymeric complex, [CuI(C(5)H(5)N(3)O)](n), the asymmetric unit is composed of one monomer unit of the polymer and one Cu(I) atom linked to one iodide anion and one pyrazine-2-carboxamide mol­ecule. The Cu(I) atom is in a distorted tetra­hedral coordination completed by one pyrazine N atom of the pyrazine-2-carboxamide ligand and three iodide anions. The polymeric structure adopts a well-known ladder-like motif of {CuNI(3)} tetra­hedra running in the b-axis direction. The mol­ecules of the organic ligand are connected via medium-to-strong N—H⋯O and N—H⋯N hydrogen bonds and weak π–π inter­actions [the distance between two parallel planes of the rings is 3.5476 (14) Å and the centroid–centroid contact is 4.080 (2) Å]. The title compound has a relatively high decomposition temperature (564 K) as a result of relatively strong covalent and non-covalent inter­actions inside and between the chains.