二维Ln-Cu配位聚合物的合成及磁弛豫行为研究  

Synthesis and magnetic relaxation behaviors of two-dimensional Ln–Cu coordinative polymers

作　　者：孙爱焕 张素铭 黄祯娜 孙豪岭[1] Ai-Huan Sun;Su-Ming Zhang;Zhen-Na Huang;Hao-Ling Sun(College of Chemistry,Beijing Normal University,Beijing 100875,China)

机构地区：[1]北京师范大学化学学院,北京100875

出　　处：《中国科学：化学》2022年第6期923-929,共7页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(编号:21671024);国家重点基础研究发展计划(编号:2013CB933402)资助项目。

摘　　要：本文中,我们使用结构基元(Cu L)(H_(2)L=N,N′-双(3-甲氧基水杨醛)-乙二胺)与稀土离子和4,4′-联吡啶-N,N′-二氧化物(bpdo)桥联配体反应,通过配位驱动自组装的方法,合成了两例具有二维“鱼骨”结构的配合物{[LnCuLCl_(2)(bpdo)_(1.5)]Cl⋅CH_(3)OH⋅3H_(2)O}(Ln=Tb(1),Dy(2)).单晶X射线衍射研究表明,两个配合物同构.其中,席夫碱配体L^(2−)连接Ln^(3+)和Cu^(2+)离子形成{LnCu}双核基元,bpdo配体与Ln^(3+)离子配位并进一步连接相邻的{LnCu}双核基元形成二维“鱼骨”结构.磁性研究表明,Ln^(3+)和Cu^(2+)离子间存在铁磁相互作用,且两个配合物分别在零场和2 kOe外磁场下表现出明显的动态磁弛豫行为,有效能垒分别为20.8(2)和14.0(4)K.In this paper,two heteronuclear complexes,{[LnCuLCl_(2)(bpdo)_(1.5)]Cl·CH_(3)OH⋅3H_(2)O}(Ln=Tb(1),Dy(2);L=N,N′-bis(2-hydroxy-3-methoxy-benzylidene)ethylenediamine;bpdo=4,4′-bipyridine-N,N′-dioxide),with a two-dimensional herringbone-like structure were synthesized by the coordination-driven self-assembly of the(Cu L)building-block with rare earth ions and the bridging ligand of bpdo.The single-crystal X-ray diffraction indicates that both complexes are isomorphic,the Ln^(3+) and Cu^(2+) ions are bridged by the L^(2−) Schiff-base ligand to form a{LnCu}-dimeric subunit,and the bpdo ligands connect the adjacent{LnCu}units to form a two-dimensional herringbone-like structure.Magnetic measurements indicate that the ferromagnetic coupling between Ln^(3+) and Cu^(2+)ions and the significant slow magnetic relaxation under zero or 2 kOe DC field with effective energy barriers of 20.8(2)and 14.0(4)K for the complex 1Tb and 2Dy,respectively.

关 键 词：稀土–过渡金属配合物 晶体结构 磁弛豫 

分 类 号：O641.4[理学—物理化学]