Bis(4-meth­oxy­benzyl­ammonium) dihydrogen diphosphate

In the title compound, 2C₈H₁₂NO⁺·H₂P₂O₇²⁻, the linked PO₄ groups of the diphosphate anion are almost eclipsed and the P—O—P angle is 134.45 (7)°. In the crystal, infinite ribbons of H₂P₂O₇²⁻ anions propagate in [100], being linked by strong O—H...O hydrogen bonds. The 4-meth­oxy­benzyl­ammonium cations bond to the diphosphate chains by N—H...O and C—H...O links, and are themselves linked by C—H...π inter­actions.

Poly[bis­(piperazine-1,4-diium) [(μ₄-cyclo-hexa­phosphato)dilithium] tetra­hydrate]

In the title compound, {(C₄H₁₂N₂)₂[Li₂(P₆O₁₈)]·4H₂O}_n, the phosphate ring anion, located around an inversion center, adopts a chair conformation. Adjacent P₆O₁₈ rings are linked via corner-sharing by LiO₄ tetra­hedra, generating anionic porous {[Li₂(P₆O₁₈)]⁴⁻}_n layers parallel to (101). The piperazine-1,4-diium cations occupy the pores and develop hydrogen bonds with the inorganic framework. An extensive network of N—H...O and O—H...O hydrogen-bonding inter­actions link the components into a three-dimensional network and additional stabilization is provided by weak C—H...O hydrogen bonds.

Bis[1-(2,3-di­methyl­phen­yl)piperazine-1,4-diium] bis­(oxonium) cyclo­hexa­phosphate dihydrate

In the title compound, 2C₁₂H₂₀N₂²⁺·2H₃O⁺·P₆O₁₈⁶⁻·2H₂O, a protonated water mol­ecule bridges the centrosymmetrical anionic P₆O₁₈ ring via O—H...O hydrogen bonds. The centrosymmetric hydrogen-bonded rings formed by four oxonium cations and four phosphate anions can be described by an R₄⁸(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...O hydrogen bonds with the O atoms of the anionic framework.

N′-(2,4-Di­nitro­phen­yl)acetohydrazide monohydrate

In the crystal structure of the title compound, C₈H₈N₄O₅·H₂O, the organic and lattice water mol­ecules are linked together via N—H...O and O—H...O hydrogen bonds. A C—H...O inter­action is also observed between the organic mol­ecules. These hydrogen bonds and inter­actions lead to the formation of a three-dimensional network. An intra­molecular N—H...O hydrogen bond also occurs. The dihedral angle between the acetyl group and the almost planar hydrazide moiety [maximum deviation from the least-squares plane is 0.209 (2) Å for one of the nitro O atoms] is 88.5 (3)°.

5-Amino-1H-1,2,4-triazol-4-ium hydrogen oxalate

In the title salt, C₂H₅N₄⁺·C₂HO₄⁻, the hydrogen oxalate anions form corrugated chains parallel to the c axis, linked by inter­molecular O—H...O hydrogen bonds. The 5-amino-1H-1,2,4-triazol-4-ium cations are connected into centrosymmetric clusters via weak C—H...N hydrogen bonds forming nine-membered rings with an R₃³(9) motif. These clusters are inter­connected via anions through N—H...O hydrogen bonds, building a three-dimensional network.