Synthesis, crystal structures and magnetic properties of the oxalate-bridged single CuIICuII and cocrystallized CuIIZnII systems. Three species (CuCu, CuZn, ZnZn) in the crystalline lattice

New oxalate-bridged compounds, [{Cu(bpy)Cl}2(μ-C2O4)] (1) and [CuZn{(bpy)Cl}2(μ-C2O4)] (2) (bpy=2,2′-bipyridine), were obtained by a non-conventional synthetic procedure. Cocrystallized compound 2 contains three types of binuclear species: [Cu(bpy)Cl(μ-C2O4)Cu(bpy)Cl], [Cu(bpy)Cl(μ-C2O4)Zn(bpy)Cl] and [Zn(bpy)Cl(μ-C2O4)Zn(bpy)Cl], in the ratio 1:2:1, respectively, as determined by magnetic measurements, and supported also by other methods.