Manipulation of Mixed Ligands to Form Single-Layer and Double-Layer Lanthanide Clusters and Their Magnetic Properties

There have been many examples of synthesizing multinuclear lanthanide clusters of special shapes, such as spherical, cage-shaped, tubular, and so on. However, synthesizing multinuclear lanthanide clusters with distinct layered structures possess a challenge. We use the ligands 2,3-dihydroxybenzaldehyde, benzohydrazide and pyridin-2-ylmethanamine to obtain a single layer of six-core lanthanide clusters [Dy-6(mu(3)-O)(mu(3)-OH)(4)(L-2)(3)( L-3)(3)(L-4)3(H2O)(3)]Cl-6 center dot CH3OH (1) and [Gd-6( mu(3)- O)(mu 3OH)(4)(L-2)(3)(L-3)(3)(L-4)(3)(H2O)(2)(CH3OH)]Cl-6 center dot CH3OH center dot 3CH(3)CN (2). The central metal ion of cluster 1 presents a triangular lattice shape. We changed the ligands to 2-hydroxy-3-methoxybenzaldehyde and 2-aminobenzoic acid and obtained the double-layer eightcore lanthanide clusters [Dy-8(mu(3)-OH)(6)(L-5)(2)(L-6)(8)] (3) and [Gd-8(mu(3)-OH)(6)(L-5)(2)(L-6)(8)]center dot 4CH(3)OH center dot CH3CN (4). The upper and lower layers of cluster 3 have four metal ions, respectively, forming a huge cavity inside the structure. This is the first time that a multinuclear lanthanide cluster with a layered structure has been constructed by the in situ reaction of mixed ligands. AC susceptibility test shows that the imaginary part signals of cluster 1 do not show frequency dependence and the imaginary part signals of cluster 3 show frequency dependence at low temperatures. By fitting the Arrhenius equation, we obtain U-eff = 2.87 K and tau(0) = 2.76 x 10(-4) s.