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席夫碱还原后配体H_2L与Dy(ClO_4)_3或YbCl_3反应得到的晶体产物经过X射线单晶衍射数据分析表明,产物分别为过氧根桥连的双核稀土化合物[Dy_2(μ-O_2)L_2]·4MeOH·2H_2O(1)和[Yb_2(μ-O_2)L2]·3MeOH·2H_2O(2)。变温直流磁化率曲线(χMT-T)以及不同温度下磁化强度与磁场关系曲线(M-H)表明1有显著的磁各向异性,2存在较强的反铁磁相互作用。1000Oe外场下化合物1不同频率的变温交流磁化率曲线出现峰值,说明1为潜在的单分子磁体,通过ln(χ″M/χ’M)对T-1作图估算出其“能垒高度”约为6.1K,指前因子τ0≈2.4×10~(-6)s。荧光光谱测量发现1和2都具有配体L2-自身发光和稀土离子的特征发光。
The X-ray single crystal diffraction data of the crystal products obtained after the reaction between H_2L and Dy (ClO_4) _3 or YbCl_3 after the reduction of Schiff base showed that the products are the peroxo-bridged dinuclear rare earth compounds [Dy_2 (μ-O_2) L_2] · 4MeOH · 2H_2O (1) and [Yb_2 (μ-O_2) L2] · 3MeOH · 2H_2O (2). The temperature-dependent DC susceptibility curve (χMT-T) and the relationship between the magnetization and the magnetic field at different temperatures (M-H) show that 1 has significant magnetic anisotropy and 2 has strong antiferromagnetic interaction. Peaks of the AC variable susceptibility curves of compounds 1 at different frequencies under the 1000 Oe field indicate that 1 is a potential single-molecule magnet and its “energy barrier height” is estimated by plotting ln (χ “M / χ’M) on T-1 ”Is about 6.1K and the pre-factor τ0 is about 2.4 × 10 ~ (-6) s. Fluorescence spectroscopy shows that both 1 and 2 have the characteristic luminescence of ligand L2-self-luminescence and rare earth ions.