基于多齿席夫碱的双核Dy(Ⅲ)配合物的合成、晶体结构和磁性

Synthesis,Crystal Structure and Magnetic Properties of Dinuclear Dy(Ⅲ)􀃮Complex Based on Multidentate Schiff Base

以2-肟基丙烷酰肼缩2-羟基萘甲醛席夫碱(H_(2)L)为主配体,乙酰丙酮(Hacac)为辅配体,构筑了一例双核稀土镝配合物[Dy_(2)(L)_(2)(acac)_(2)(CH_(3)CH_(2)OH)_(2)](1)。通过单晶X射线衍射、元素分析以及磁性测试对其结构和磁行为进行了表征。结构分析表明,配合物1是一个结构呈中心对称的双核镝(Ⅲ)配合物,其结构的最小不对称单元包含1个Dy(Ⅲ)离子,1个L^(2-)配体,1个acac-配体和1个乙醇分子;中心Dy(Ⅲ)离子为八配位,其配位构型为扭曲的双帽三棱柱。磁性研究结果表明,配合物1中Dy(Ⅲ)离子间存在弱的反铁磁相互作用,且该配合物表现出了慢磁弛豫行为,其磁弛豫有效能垒为14.52 K,指前因子τ_(0)为7.58×10^(-6) s。

A new Dy_(2) complex[Dy_(2)(L)_(2)(acac)_(2)(CH_(3)CH_(2)OH)_(2)](1)has been synthesized based on a multidentate Schiff base H_(2)L(H_(2)L=N′-(2-hydroxynaphthalen-1-ylmethylene)-2-(hydroxyimino)propanehydrazide)andβ-diketone coligand Hacac(Hacac=acetylacetone).Complex 1 was characterized by single-crystal X-ray diffraction,elemental analysis and further investigated by magnetic measurements.Structural analysis reveals that complex 1 is a centrosymmetric dinuclear dysprosium complex and the asymmetric unit contains a Dy(Ⅲ)ion,one L^(2-) ligand,one acac-coligand,and an ethanol molecule.Each of the Dy(Ⅲ)centers is eight-coordinate and adopts a distorted bicapped trigonal-prismatic coordination geometry.Magnetic studies suggest the existence of weak antiferromagnetic interactions between the Dy(Ⅲ)ions in 1.In addition,the slow magnetic relaxation behaviors are observed in 1 with the magnetic energy barrierΔE/kB=14.52 K and the pre-exponential factor τ_(0)=7.58×10^(-6)s.CCDC:2096910.