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The syntheses, structures, and magnetic properties of two series of Cr-Ln heterometallic clusters based on the 2,2'-bipyridine (bipy) ligand are reported; binuclear [LnCr(bipy)2-(µ2-OH)2(H2O)6](ClO4)4·2H2O {Ln = Gd (1Gd) or Dy (1Dy)} and trinuclear [LnCr2(bipy)4(µ2-OH)4(H2O)4](ClO4)5·H2O {Ln = Gd (2Gd), Dy (2Dy), or Tb (2Tb)}. Their syntheses could be controlled by the amount of lanthanide perchlorate used. The binuclear [CrLn] clusters could be formed with 24 equivalents of Ln(ClO4)3, whereas 12 equivalents of Ln(ClO4)3 gave the trinuclear [Cr2Ln] species with a CrLnCr core. The Cr3+ and Ln3+ ions are bridged by µ2-OH groups in the two systems, and the [Cr2Ln] cluster is further assembled into a 1D supramolecular architecture by weak intermolecular p-p interactions. Magnetic analyses reveal that the Cr···Gd interactions in 1Gd and 2Gd are both antiferromagnetic. [ABSTRACT FROM AUTHOR]

Abstract: An unusual heterotrinuclear complex [LCo(μ-L1, 1-N3)2(μ-L1)Ni(μ-1, 1-N3)2(μ-L1)CoL] (1) was obtained by the reaction of the precursor of half-sandwich nickel(II) complex [LNi(HL1)2(N3)] (2) and CoCl2 ·6H2O (L=hydrotris(3,5-dimethylpyrazolyl)borate; L1 =3,5-dimethylpyrazolate), the complex 1 was characterized by X-ray single-crystal diffraction, elemental analysis, IR, UV–vis spectra and magnetic properties. [Copyright &y& Elsevier]

The crystal structures of compounds (III) and (IV) are determined by single crystal XRD. [ABSTRACT FROM AUTHOR]