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.

4-Methyl­benzyl­ammonium nitrate

In the title salt, C₈H₁₂N⁺·NO₃⁻, the N atom of the 4-methyl­benzyl­ammonium cation is displaced by 1.366 (2) Å from the mean plane of the other atoms. In the crystal, the cations are connected to the anions by N—H...O and N—H...(O,O) hydrogen bonds, generating a layered network parallel to (100). A weak C—H...O inter­action also occurs.

2,3-Xylidinium nitrate

In the crystal structure of the title compound, C₈H₁₂N⁺·NO₃⁻, the 2,3-xylidinium (2,3-di­methyl­anilinium) cations are connected to the nitrate anions through bifurcated N—H...(O,O) and weak C—H...O hydrogen bonds, generating corrugated layers parallel to (001) at z = 0.25 and 0.75. These layers are connected via C—H...O inter­actions, giving rise to a three-dimensional network.