cis-(Acetato-κ(2)O,O')(5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-decane-κ(4)N,N',N'',N''')nickel(II) perchlorate monohydrate.

The complete cation in the title hydrated mol-ecular salt, [Ni(CH(3)CO(2))(C(16)H(36)N(4))]ClO(4)·H(2)O, is generated by the application of crystallographic twofold symmetry; the perchlorate anion and water mol-ecule are each disordered around a twofold axis. The Ni(II) atom exists within a cis-N(4)O(2) donor set based on a strongly distorted octa-hedron and defined by the four N atoms of the macrocyclic ligand and two O atoms of a symmetrically coordinating acetate ligand. In the crystal, hydrogen bonding (water-acetate/perchlorate O-H⋯O and amine-perchlorate N-H⋯O) leads to layers in the ab plane. The layers stack along the c axis, being connected by C-H⋯O(water) inter-actions. The crystal studied was found to be a non-merohedral twin; the minor component refined to 15.9 (6)%.