【摘 要】
：
Two isostructural tetranuclear lanthanide clusters named [Ln4(L)4(CH3O)4]·CH3OH (Ln = Gd(III) for 1, Dy(III) for 2, H2L = N'-(2-hydroxy-3-methoxybenzylidene)-6
【机 构】
：
Henan Key Laboratory of Function-Oriented Porous Materials,College of Chemistry and Chemical Enginee
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Two isostructural tetranuclear lanthanide clusters named [Ln4(L)4(CH3O)4]·CH3OH (Ln = Gd(III) for 1, Dy(III) for 2, H2L = N'-(2-hydroxy-3-methoxybenzylidene)-6-(hydroxymethyl) picolinohydrazide) were successfully isolated by using a polydentate Schiff based ligand and Ln(III) nitrate salts. The structures of 1 and 2 were characterized by X-ray structural analyses, they are held by four double deprotonated li-gands L2-. In them all the lanthanide ions are eight-coordinated and distributed over four vertices of a parallelogram, presenting a Ln4 cluster with a strict [2 × 2] square grid pattern. The details of magnetic analysis show that 1 displays weak anti-ferromagnetic exchange between neighboring Gd(III) ions through carboxylate oxygen and methanol oxygen ligand atoms. Furthermore, 1 exhibits significant magnetocaloric effect with the maximum entropy change-△Sm value of 28.5 J/(kg·K) for△H=7.0 T at 2.0 K. For compound 2, remarkable slow magnetic relaxation behaviors are observed in the presence of zero magnetic field withτ0=1.02 × 10-6 s and energy barrier△E/kB= 43.24 K.
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