一个新颖的沙漏型九核镝(Ⅲ)簇合物:合成、结构和磁性能

A novel sandglass-shaped Dy_9 cluster:Synthesis,structure,and magnetism

以2-羟基苯乙酮(HAP)为配体,采用常温挥发的方法合成了一个新颖的的沙漏型九核镝(Ⅲ)簇合物{[Dy9(μ3-OH)8(μ4-OH)2(AP)16]Cl},通过单晶和粉末X-线衍射、元素分析、红外光谱、热重分析、直流和交流变温磁化率分析对其结构和磁性能进行了全面表征.晶体结构测定结果表明:该簇合物结晶于三斜的Pī空间群,a=1.535 70(3)nm,b=2.262 32(4)nm,c=2.360 69(3)nm,α=84.287 5(13)°,β=73.944 8(14)°,γ=70.960 0(16)°,V=7.450 1(2)nm3,Z=2.该簇合物中10个羟基聚集9个稀土镝(Ⅲ)离子形成1个沙漏型Dy9内核结构,外围通过16个带负电荷的AP-配体进一步加固.磁性能测量结果表明,簇合物内镝(Ⅲ)离子间存在着弱的反铁磁相互作用,零场下呈现磁矩的慢弛豫行为,磁矩自旋翻转的有效能垒和指前因子分别为3.5 K和2.9×10^(-6) s.

A novel Dy9 cluster with 2-hydroxyacetophenone(HAP)ligand,[Dy9(μ3-OH)8(μ4-OH)2(AP)16]Cl,was synthesized by room-temperature evaporation method.The crystal structure,thermal stability and magnetic property of the complex were characterized by single-crystal and powder X-ray diffraction,elemental analysis,FT-IR spectrum,TG and variable-temperature direct-and alternating current magnetic susceptibility.The determination of the crystal structure showed that the cluster crystallizes in the triclinic Pīspace group with a=1.535 70(3)nm,b=2.262 32(4)nm,c=2.360 69(3)nm,α=84.287 5(13)°,β=73.944 8(14)°,γ=70.960 0(16)°,V=7.450 1(2)nm3 and Z=2.In the cluster,nine separate Dy(Ⅲ)ions are connected into a closed sandglass-shaped cluster by ten hydroxyl groups,which is further reinforced by sixteen negatively charged AP-ligands.The weak antiferromagnetic reaction occurs among Dy(Ⅲ)ions,and the cluster exhibits slow magnetic relaxation behavior.The effective energy barrier is 3.5 K,and the preexponential factor is 2.9×10^-6 s.