Five Rare μ₄‐O‐Centered Ln₆ Clusters with Single‐Molecule Magnet Behavior for Dy₆

Abstract

Five hexanuclear lanthanide clusters of composition [Ln (μ -O) (HCOO) L (HL') (dmf) ] [Ln=Dy (1), Er (2), Ho (3), Tb (4), Gd (5); H L=2-{[2-(hydroxymethyl)phenylimino]methyl}-6-methoxyphenol; H L'=3-{[2-(hydroxymethyl)phenylimino]methyl}benzene-1,2-diol; H L' was derived in situ from the H L ligand] were prepared under solvothermal conditions. The [Ln ] cores of 1-5 possess an unprecedented motif, namely, two tetrahedron Ln units sharing an edge and two vertices. The six Ln ions of 1-5 are connected through two μ -O anions. Magnetic susceptibility studies reveal that complex 1 exhibits frequency dependence of the alternating current susceptibility typical of single-molecule magnets. Complex 1 possesses a relatively large energy barrier of 85 K among all of the reported Dy single-molecule magnets.

Lanthanide Tetranuclear Cage and Mononuclear Cocrystalline Nitronyl Nitroxide Complex with Single-Molecule-Magnet Behavior

“…Among the lanthanide metal ions, the Dy III ion has undoubtedly given the largest quantity of pure 4f SMMs, owing to the intrinsic large magnetic moment with a Kramers doublet ground state of 6 H 15/2 and the strong Ising-type magnetic anisotropy . Until now, various mononuclear, − dinuclear, − trinuclear, − tetranuclear, ,− and polynuclear − dysprosium-based SMMs have been reported, among which the highest effective energy barrier of a Dy 5 pyramid cluster was up to 528 K . However, polynuclear SMMs based on pure lanthanide metal ions are comparatively rare because of the difficulty in furthering magnetic coupling between the orbital of the bridging ligand and the 4f orbital of the Ln III ions.…”

Single‐Molecule Magnetism in Dy2 Cluster Based on a Schiff Base Ligand

“…[ 3 ] Many lanthanide SMMs with varying ranges of nuclearities have been prepared. [ 4–10 ] Among all the lanthanide‐based SMMs, [Ln 2 ]SMMs have attracted significant attention of the chemists and physicists in the world. [ 11–40 ] There are many reasons for this, for example, (i) compared with other polynuclear clusters, the synthesis of [Ln 2 ] is easier to control; (ii) the structure‐property relationships of the dinuclear systems could be easily investigated by modifying the functional groups of the ligands; (iii) in studying the magnetic interaction between two lanthanide atoms, they represent the simplest structural units; and (iv) it is relatively convenient to determine the possible orientation of anisotropy in the dinuclear system.…”