A triple-bridged azido-Cu(II) chain compound fine-tuned by mixed carboxylate/ethanol linkers displays slow-relaxation and ferromagnetic order: synthesis, crystal structure, magnetic properties and DFT calculations.
A triple-bridged azido-Cu(II) chain compound fine-tuned by mixed carboxylate/ethanol linkers displays slow-relaxation and ferromagnetic order: synthesis, crystal structure, magnetic properties and DFT calculations.
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DOI：
10.1039/c4dt02195a
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发表时间：
2014-09
影响因子：
4
通讯作者：
Xiangyu Liu;Sanping Chen;Thais Grancha;E. Pardo;Hongshan Ke;Bing Yin;Q. Wei;G. Xie;Sheng-li Gao
中科院分区：
文献类型：
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作者：
Xiangyu Liu;Sanping Chen;Thais Grancha;E. Pardo;Hongshan Ke;Bing Yin;Q. Wei;G. Xie;Sheng-li Gao
合成并表征了一种新的叠氮铜配合物[Cu（4-fba）（N3）（C2 H5 OH）]（4-fba = 4-氟苯甲酸）（1）。X-射线晶体结构分析表明，1的不对称单元中只有一个晶体学上独立的Cu（II）离子，呈现伸展的八面体构型，其中两个叠氮基N原子和两个羧基O原子位于赤道正方形，而两个乙醇O原子位于顶点位置，形成一个由EO-叠氮基、syn、syn-羧基和μ2-乙醇交替组成的三维Cu（II）链.标题化合物由铁磁相互作用的铁磁链组成，具有铁磁有序性（T（c）= 7.0K）。每个链内相邻的Cu（II）离子之间的强铁磁耦合是由于超交换途径的反互补性，而铁磁链间相互作用-负责长程磁有序-最有可能是由于存在协调的乙醇分子与相邻链建立氢键。对化合物1进行了DFT计算，对磁性行为提供了定性的理论解释。
A new azido-Cu(II) compound, [Cu(4-fba)(N3)(C2H5OH)] (4-fba = 4-fluorobenzoic acid) (1), has been synthesized and characterized. The X-ray crystal structure analysis demonstrates that only one crystallographically independent Cu(II) ion in the asymmetric unit of 1 exhibits a stretched octahedral geometry in which two azido N atoms and two carboxylic O atoms locate in the equatorial square, while two ethanol O atoms occupy the apical positions, forming a 1D Cu(II) chain with an alternating triple-bridge of EO-azido, syn,syn-carboxylate, and μ2-ethanol. The title compound consists of ferromagnetically interacting ferromagnetic chains, which exhibit ferromagnetic order (T(c) = 7.0 K). The strong ferromagnetic coupling between adjacent Cu(II) ions within each chain is due to the countercomplementarity of the super-exchange pathways, whereas the ferromagnetic interchain interactions--responsible for the long-range magnetic ordering--are most likely due to the presence of coordinated ethanol molecules establishing hydrogen bonds with neighboring chains. DFT calculations have been performed on compound 1 to offer a qualitative theoretical explanation of the magnetic behavior.