Bis[1,1'-(1,3-phenyl-enedimethyl-ene)di(1H-imidazol-3-ium)] β-octa-molybdate.

In the title compound, (C14H16N4)2[Mo8O26], the β-octa­molybdate anion is centrosymmetric. N—H⋯O hydrogen bonds link the diimidazolium cations and the polyoxidoanions into a chain structure along [100]. π–π inter­actions between the imidazole rings and between the imidazole and benzene rings [centroid–centroid distances = 3.611 (2) and 3.689 (3) A, respectively] connect the chains.