IN THE CRYSTAL STRUCTURE OF THE TITLE COMPOUND [SYSTEMATIC NAME: 1-methyl-piperazine-1,4-diium bis-(2,4,6-trinitro-phen-ol-ate)], C(5)H(14)N(2) (2+)·2C(6)H(2)N(3)O(7) (-), the ionic components are connected by relatively strong N-H⋯O hydrogen bonds into centrosymmetric six-membered conglomerates, which comprise two dications and four anions. Besides Coulombic inter-actions, only weak C-H⋯O inte...

The asymmetric unit of the title compound, (C(11)H(18)N(2))(2)[CdCl(6)]·2H(2)O, consists of one 1-benzyl-piperazine-1,4-diium dication, one water mol-ecule and one-half of a [CdCl(6)](4-) anion, located on an inversion centre. The crystal packing is governed by an extensive three-dimensional network of inter-molecular O-H⋯Cl, C-H⋯Cl, N-H⋯O and N-H⋯Cl hydrogen bonds, two of them bifurcated.

The title compound, (C(5)H(14)N(2))[CuCl(4)], was synthesized by hydro-thermal reaction of CuCl(2) with 1-methyl-piperazine in an HCl/water solution. Both amine N atoms are protonated. The piperazine ring adopts a chair conformation. The Cu-Cl distances in the tetrahedral anion are in the range 2.2360 (7)-2.2732 (7) Å. In the crystal, moderately strong and weak inter-molecular N-H⋯Cl hydrogen b...