Synthesis and crystal structure of bis-[-di-aqua-(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ , , , )nickel(II)] -(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ , , , )bis-[4,4',4''-(1,3,5-tri-methyl-benzene-2,4,6-tri-yl)tris-(hydrogen phenyl-phospho-nato-κ)]nickel(II) deca-hydrate.

The components of the title compound, [Ni(CHN)(HO)][Ni(CHN)(CHOP)]·10HO are two centrosymmetric [Ni(CHN)(HO)] dications, a centrosymmetric [Ni(CHN)(CHOP)] tetra-anion and five crystallographically unique water mol-ecules of crystallization. All of the nickel ions are coordinated by the four secondary N atoms of the macrocyclic cyclam ligands, which adopt the most energetically stable -III conformation, and the mutually O atoms of either water mol-ecules in the cations or the phospho-nate groups in the anion in a tetra-gonally distorted NiNO octa-hedral coordination geometry. Strong O-H⋯O hydrogen bonds between the protonated and the non-protonated phospho-nate O atoms of neighboring anions result in the formation of layers oriented parallel to the plane, which are linked into a three-dimensional network by virtue of numerous N-H⋯O and O-H⋯O hydrogen bonds arising from the -NH groups of the macrocycles, phospho-nate O atoms and coordinated and non-coordinated water mol-ecules.