Benzoic acid–2,2′-biimidazole (2/1)

In the title compound, C(6)H(6)N(4)·2C(7)H(6)O(2), the asymmetric unit contains a half-mol­ecule of biimidazole and one benzoic acid mol­ecule. The unit cell contains two biimidazole mol­ecules and four benzoic acid mol­ecules, giving the reported 2:1 ratio of benzoic acid to biimidazole. The biimidazole mol­ecule is located on an inversion center (passing through the central C—C bond). Strong N—H⋯O and O—H⋯N hydrogen bonds link the benzoic acid mol­ecules with the neutral biimidazole mol­ecules, which lie in planar sheets. In the crystal packing, the parallel sheets are related by a twofold rotation axis and an inversion centre, respectively, forming an inter­woven three-dimensional network via weak C=O⋯π inter­molecular inter­actions between neighboring mol­ecules.