Abstract
In the title compound, 2C(12)H(20)N(2)(2+)center dot 2H(3)O(+)center dot P6O186-center dot 2H(2)O, a protonated water molecule bridges the centrosymmetrical anionic P6O18 ring via O-H center dot center dot center dot O hydrogen bonds. The centrosymmetric hydrogen-bonded rings formed by four oxonium cations and four phosphate anions can be described by an R-4(8)(36) graph-set motif. The ring motifs are connected by hydrogen bonds into inorganic layers perpendicular to [100]. The 1-(2,3-dimethylphenyl) piperazine-1,4-diium cations are located between the layers, compensating their negative charge and establishing N-H center dot center dot center dot O hydrogen bonds with the O atoms of the anionic framework.