Two bimetallic layered materials with “Cu4Fe3” defective cubane units: syntheses, structures and magnetic properties of {[CuII(tn)]2[FeII(CN)6]}3·[Na3FeIII(CN)6]·12H2O (1) and {[CuII(tn)]2[FeII(CN)6]}·KCl·5H2O(2)

Reactions of the [FeIII(CN)6]3− anion with the [CuII(tn)]2+ ion (tn = 1,3-diaminopropane) afford the compounds {[CuII(tn)]2[FeII(CN)6]}3·[Na3FeIII(CN)6]·12H2O (1) and {[Cun(tn)]2[FeII(CN)6]}·KCl·5H2O (2). Despite the differences concerning their asymmetric units, both structures present strong similar features: in both structures, the Cu(II) ion presents a square-base pyramidal CuN5 environment and each [FeII(CN)6]4− anion is linked to six Cu(II) ions through its six N atoms leading to infinite [CuII(tn)]2[FeII(CN)6] layers which can be viewed as 2-D layered arrangement generated by the defective cubane units Cu4Fe3 involving Fe-CN-Cu bridges. The most important differences between the two structures concern essentially the inter-layer arrangement which is occupied, in compound 1, by isolated paramagnetic [Fe(CN)6]3− anions and water molecules, while in compound 2, this interlayer space is occupied by K+, Cl− ions and water molecules. Magnetic data indicate for 1 weak antiferromagnetic interactions and presence of magnetically isolated [FeIII(CN)6]3−anion and for 2 weak ferromagnetic interactions between the Cu(II) ions.