catena-Poly[[[tetraaquairon(II)]-μ-5,5′-diazenediylditetrazolido] dihydrate]

In the title compound, {[Fe(C2N10)(H2O)4]·2H2O}n, the coordination geometry around the Fe(II) atom, which lies on a center of inversion, is distorted octahedral, with bonds to four O atoms and two N atoms. The azotetrazolate ligand displays a bridging coordination mode, forming an infinite zigzag chain. Intermolecular O—H...O and O—H...N hydrogen bonding and offset face-to-face π–π stacking interactions [centroid–centroid distance = 3.4738 (13) ] lead to a three-dimensional network.