2-Methyl­benzene-1,3-di­ammonium dinitrate

In the crystal structure of the title salt, C₇H₁₂N₂²⁺·2NO₃⁻, the nitrate ions are located in the vicinity of the protonated amine groups, accepting strong N—H...O hydrogen bonds. Each ammonium group is involved in a total of three such inter­actions with neighbouring nitrate ions, generating a three-dimensional network. In addition, there are π–π inter­actions between the aromatic rings of centrosymmetrically related di­ammonium moieties, with a centroid–centroid distance of 3.682 (1) Å.

Bis[tris(propane-1,3-diamine-κ²N,N′)­nickel(II)] di­aqua­bis(propane-1,3-di­amine-κ²N,N′)nickel(II) hexa­bromide dihydrate

In the title compound, [Ni(C₃H₁₀N₂)₃]₂[Ni(C₃H₁₀N₂)₂(H₂O)₂]Br₆·2H₂O, one Ni²⁺ cation, located on an inversion centre, is coordinated by four N atoms from two ligands and by two water O atoms. The other Ni²⁺ cation, located in a general position, is coordinated by six N atoms from three ligands. In both cases, the Ni²⁺ cation has an octa­hedral coordination environment. The overall structural cohesion is ensured by three types of hydrogen bonds, N—H...Br, O—H...Br and O—H...O, which connect the two types of complex cations, the bromide counter-anions and the lattice water molecules into a three-dimensional network.