Hydroxonium hydrate tris(2,4,6-triamino-1,3,5-triazin-1-ium) bis[bis(pyridine-2,6-dicarboxylato)manganate(II/III)] hydroxide pyridine-2,6-dicarboxylic acid solvate pentahydrate

For charge balance in the title compound, (H5O2)(C3H7N6)(3)[Mn(C7H3NO4)(2)](2)(OH)center dot C7H5NO4 center dot 5H(2)O, it is assumed that the metal atom site is disordered Mn-II/Mn-III, probably due to partial air oxidation of the starting Mn II species. The formula unit of the complex contains a hydroxonium hydrate cation, H5O2+, also known as the Zundel cation, with twofold symmetry. The O center dot center dot center dot O [2.445 (10) angstrom] and O center dot center dot center dot H distances [1.24 (2) angstrom] in the H5O2+ cation indicate a strong hydrogen bond. In addition, there is a hydroxide ion that is disordered with respect to a twofold rotation axis. One of the melaminium groups and the pyridine-2,6-dicarboxylate (pydc) ligand also reside on crystallographic twofold axes. The coordination environment of the Mn ion is distorted octahedral. Three intermolecular C=O center dot center dot center dot pi interactions are observed, with distances of 3.536 (4), 3.262 (4) and 3.750 (4) angstrom between carboxylate C=O groups and the centroids of the aromatic rings of pydc and melaminium. There are numerous O-H center dot center dot center dot O, O-H center dot center dot center dot N, N-H center dot center dot center dot O, N-H center dot center dot center dot N and C-H center dot center dot center dot O hydrogen bonds. Most of the components of the structure are organized into one plane.