ChemInform Abstract: Structure and Electrochemical Properties of Antiferromagnetically Coupled Binuclear Hydroxo‐Bridged Copper(II) Complexes with Pyridazine and Phthalazine Ligands. Crystal and Molecular Structures of (μ‐3,6‐Bis(1‐pyrazolyl)pyridazine‐N2,μ‐N3,μ‐N4,N5)(μ‐hydroxo)trichl# oroaquodicopper(II)‐0.8‐Water, Cu2C10H11Cl3N6O2·0.8 H2O, (μ‐3,6‐Bis(1‐pyrazolyl)pyridazine‐N2,μ‐N3,μ‐N4,N5)(μ‐hydroxo)tribro# moaquodicopper(II)‐0.6‐Water, Cu2C10H11Br3N6O2·0.6 H2O, and (μ‐1,4‐Bis(1‐methyl‐2‐imidazolyl)phthalazine)(μ‐hydroxo)tribromoaquodicop# per(II)‐Water, Cu2C16H17Br3N6O3·H2O.

Abstract The structures of the title complexes (Ia) and (Ib) (for both space group P1, Z=2) and (II) ( P2 1 /n, Z=4), prepared by previously described methods, are determined by X‐ray analysis.