Di-aqua-bis-{μ-1,5-bis-[(pyridin-2-yl)methyl-idene]carbonohydrazide(1-)}di-μ-chlorido-tetra-chlorido-tetra-zinc(II).

A tetra-nuclear Zn(II) complex, [Zn(4)(C(13)H(11)N(6)O)(2)Cl(6)(H(2)O)(2)] or {[Zn(2)(HL)(H(2)O)(Cl(2))](μCl)(2)[Zn(2)(HL)(H(2)O)(Cl)]}(2), was synthesized by mixing an equimolar amount of a methanol solution containing ZnCl(2) and a methanol solution containing the ligand H(2) L [1,5-bis-(pyridin-2-yl-methyl-ene)carbono-hydrazide]. In the tetra-nuclear complex, each of the two ligand mol-ecules forms a dinuclear unit that is connected to another dinuclear unit by two bridging chloride anions. In each dinuclear unit, one Zn(II) cation is penta-coordinated in a N(2)OCl(2) in a distorted square-pyramidal geometry, while the other Zn(II) cation is hexa-coordinated in a N(3)OCl(2) environment with a distorted octa-hedral geometry. The basal plane around the penta-coordinated Zn(II) cation is formed by one chloride anion, one oxygen atom, one imino nitro-gen atom and one pyridine nitro-gen atom with the apical position occupied by a chloride anion. The basal plane of the hexa-coordinated Zn(II) cation is formed by one chloride anion, one hydrazinyl nitro-gen atom, one imino nitro-gen atom and one pyridine nitro-gen atom with the apical positions occupied by a water oxygen atom and a bridged chloro anion from another dinuclear unit, leading to a tetra-nuclear complex. A series of intra-molecular C-H⋯Cl hydrogen bonds is observed in each tetra-nuclear unit. In the crystal, the tetra-nuclear units are connected by inter-molecular C-H⋯Cl, C-H⋯O and N-H⋯O hydrogen bonds, forming a planar two-dimensional structure in the ac plane.