异金属镧系（III）-钴（II）配位聚合物的自组装：合成、结构及磁性研究

Self-assembly of heterometallic Ln(III)-Co(II) coordination polymers: syntheses, structures, and magnetic studies.

作者信息

Zhao Xiao-Qing, Liu Xu-Hui, Kang Xiao-Min, Zhao Bin

机构信息

Department of Chemistry, Key Laboratory of Advanced Energy Material Chemistry of the Ministry of Education, and Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China.

出版信息

Dalton Trans. 2015 Nov 21;44(43):18856-63. doi: 10.1039/c5dt02280k.

DOI:10.1039/c5dt02280k

PMID:26460817

Abstract

A family of heterometallic 4f-3d coordination polymers with the common formula [LnCo1.5(L)2(H2O)5]n (Ln = Pr(1), Eu(2), Gd(3), Tb(4), Dy(5), Ho(6), and Er(7), and H3L = 4-(carboxymethoxy)isophthalic acid) was obtained under solvothermal conditions with the effect of NaN3, which was involved in the reactions but not in the final structure. All of the compounds were isostructural, and had a two-dimensional wave-like structure based on centrosymmetric [LnO2Co]-Co-[LnO2Co] motifs. The results of the magnetic measurements displayed that ferromagnetic interactions occurred in the frameworks (3-7) containing "heavy" lanthanide ions (Gd, Tb, Dy, Ho, and Er), which should be ascribed to the coupling between the Ln(III) and Co(II) ions. Furthermore, compound 5, containing Dy(III) ions, displayed field-induced slow magnetic relaxation.

摘要

在NaN₃的作用下，通过溶剂热法得到了通式为[LnCo₁.₅(L)₂(H₂O)₅]ₙ（Ln = Pr(1)、Eu(2)、Gd(3)、Tb(4)、Dy(5)、Ho(6)和Er(7)，H₃L = 4-(羧基甲氧基)间苯二甲酸）的一系列异金属4f-3d配位聚合物，NaN₃参与了反应但不在最终结构中。所有化合物均为同构，基于中心对称的[LnO₂Co]-Co-[LnO₂Co]基序具有二维波浪状结构。磁性测量结果表明，在含有“重”镧系离子（Gd、Tb、Dy、Ho和Er）的骨架（3 - 7）中发生了铁磁相互作用，这应归因于Ln(III)和Co(II)离子之间的耦合。此外，含有Dy(III)离子的化合物5表现出场诱导的慢磁弛豫。