Citation: Xiao-Li GAO, Wen-Ting LEI, Qing-Fang ZHANG, Yu ZHOU, Xiao-Min KANG. Crystal Structures and Magnetic Properties of Ln2 Complexes Based on a Polydentate Schiff Base Ligand[J]. Chinese Journal of Inorganic Chemistry, ;2022, 38(1): 145-152. doi: 10.11862/CJIC.2022.002 shu

Crystal Structures and Magnetic Properties of Ln2 Complexes Based on a Polydentate Schiff Base Ligand

  • Corresponding author: Xiao-Min KANG, kangxm2020@163.com
  • Received Date: 4 June 2021
    Revised Date: 23 October 2021

Figures(8)

  • Three new Ln2 complexes based on a polydentate Schiff base ligand, namely [Ln2(L)2(acac)2(CH3OH)2]·2CH3OH (Ln=Sm (1), Gd (2), Ho (3), H2L=pyridine-2-carboxylic acid (1-methyl-3-oxo-butylidene)-hydrazide, Hacac =acetylacetone), have been synthesized by using solvothermal method. The crystal structures and magnetic properties of these complexes have been systematically studied. The crystal structures measurement results reveal that complexes 1-3 are isostructural and each eight-coordinated Ln (Ⅲ) ion possesses a square antiprism geometry; the adjacent central rare earth Ln(Ⅲ) ions are connected by two μ2-O to form a parallelogram [Ln2O2] core. The magnetic study showed that complex 2 displayed significant magnetic refrigeration property with a larger magnetic entropy (-ΔSmax) of 31.9 J·K-1·kg-1 at ΔH=70 kOe and T=2.0 K; while complex 3 shows slow magnetic relaxation behavior.
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