Synthesis of two lanthanide clusters LnIII4 (Gd4 and Dy4) with [2 × 2] square grid shape: Magnetocaloric effect and slow magnetic relaxation behaviors
| Autor: | Chen-Juan Fan, Zhilei Wu, Baoming Ji, Wenmin Wang, Chunying Xu, Li-Li Yan |
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| Rok vydání: | 2021 |
| Předmět: |
Lanthanide
Denticity Materials science Ligand 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences chemistry.chemical_compound Crystallography chemistry Geochemistry and Petrology Magnetic refrigeration Cluster (physics) Hydroxymethyl Carboxylate Isostructural 0210 nano-technology |
| Zdroj: | Journal of Rare Earths. 39:1082-1088 |
| ISSN: | 1002-0721 |
| Popis: | 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 ligands 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 –ΔSm value of 28.5 J/(kg·K) for ΔH = 7.0 T at 2.0 K. For compound 2, remarkable slow magnetic relaxation behaviors are observed in the presence of zero magnetic field with τ0 = 1.02 × 10−6 s and energy barrier ΔE/kB = 43.24 K. |
| Databáze: | OpenAIRE |
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