4,4′-Methylenedianilinium hemi(cyclotetraphosphate)

The title compound, C13H16N22+ center dot 0.5P(4)O(12)(4-), has been prepared at room temperature and studied by single-crystal X-ray diffraction. The asymmetric unit consists of one 4,4'-diphenylmethylendiammonium organic cation and two PO4 tetrahedra that form one half of a cyclic P4O124- anion that lies about an inversion centre. The P4O12 rings are linked through N - H (...) O hydrogen bonds to build layers parallel to the ab plane. The two NH3+ groups at the 4- and 4'-positions of the cations link these layers into a three-dimensional network.