摘要
为进一步研究耦合作用对自旋弛豫的影响,以五水合硝酸镝、六水合硝酸锌及配体为起始物,二甲基甲酰胺(DMF)为溶剂,合成了新的双核Dy配合物[Dy_2Zn_2(L)_4(NO_3)_2(DMF)_2](1)。X射线单晶衍射结果表明,该化合物结晶于单斜晶系,P2_1/n空间群。直流磁化率测试结果表明双核Dy之间具有铁磁耦合相互作用;零场条件下该化合物交流磁化率表现出频率依赖性质,是1个典型的单分子磁体。通过拟合得到该化合物零场时有效能垒为261K,弛豫时间为2.38×10~(-8)s。
To gain a deep insight into the impact of coupling interaction on spin relaxation,a new dinuclear Dy(Ⅲ)-based complex[Dy_2Zn_2(L_4(NO_3)_2(DMF)_2](1)was synthesized using Dy(NO_3)_3 ·5 H_2O,Zn(NO_3)_2 ·6H_2O and(E)-2-ethoxy-6-(((2-hydroxyphenyl)imino)methyl)phenol as starting materials.X-ray diffraction(XRD)measurement reveals that complex1 crystallizes in the monoclinic space group P2_1/n.Direct current(DC)magnetic properties for complex1 indicate the existence of ferromagnetic dipolar interaction between Dy(Ⅲ)ions.AC susceptibility measurements show that both in-phase(χ)and out-of-phase(χ″)susceptibility are frequency-dependent under zero dc field,which is the typical feature of single-molecule magnets(SMMs).The energy barrier and relaxation time are fitted to be 261 Kand 2.38×10~(-8) s,respectively.
引文
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