Bis­(3,5-diamino-4H-1,2,4-triazol-1-ium) 3,4-dioxocyclo­butane-1,2-diolate

The asymmetric unit of the title compound, 2C₂H₆N₅⁺·C₄O₄²⁻, contains two 3,5-diamino-4H-1,2,4-triazolium cations and one squarate dianion. The squaric acid mol­ecule donated one H atom to each of the two 3,5-diamino-1,2,4-triazole mol­ecules at their N atoms. The squaric acid dianion has four C—O bonds which are shorter than a normal single C—O bond (1.426 Å) and are slightly longer than a normal C=O bond (1.23 Å), which indicates the degree of electron delocalization in the dianion. In the crystal, the cations and dianions are linked by N—H...N and N—H...O hydrogen bonds into a three-dimensional network.