Four one-dimensional lanthanide-phenylacetate polymers exhibiting luminescence and magnetic cooling/spin-glass behavior
Four one-dimensional lanthanide-phenylacetate polymers exhibiting luminescence and magnetic cooling/spin-glass behavior
复制标题
DOI：
10.1039/c7dt03562d
复制
发表时间：
2017-12-21
影响因子：
4
通讯作者：
Cao, Guang-Xiu
中科院分区：
文献类型：
--
作者：
Li, Zhong-Yi;Xu, Ya-Lan;Cao, Guang-Xiu
在水热条件下合成了4种含苯乙酸酯(PAA(-))配体的稀土等结构配位聚合物[Ln(PAA)(3)(H2O)](N)(Ln=Eu(1)；Gd(2)；Tb(3)；Dy(4))。配合物1-4通过苯丙二酸的原位脱羧基生成的PAA(-)配体的羧酸桥联形成一维波链结构。磁性研究表明，在1-4的一维链中存在铁磁性Ln…Ln耦合。同时，2具有显著的低温磁热效应，在3K和7T下的最大增量S-m为26.73.3和4表现出有趣的自旋玻璃行为，这在含Ln的配合物中很少有报道.此外，化合物1和3的固体光物理性质在可见光区显示出较强的Eu3+和Tb3+发光特征，表明Eu和Tb基发光是通过从配体到金属中心的有效能量传递而敏化的。
Four isostructural lanthanide coordination polymers with a phenylacetate (PAA(-)) ligand, [Ln(PAA)(3)(H2O)](n) (Ln = Eu (1); Gd (2); Tb (3); Dy (4)), were synthesized under hydrothermal conditions. Complexes 1-4 display a one-dimensional (1D) wave chain structure bridged by the carboxylate of the PAA(-) ligand, which was generated via the in situ decarboxylation of phenylmalonic acid. Magnetic studies suggest the presence of ferromagnetic Ln...Ln coupling in the 1D chain of 1-4. Meanwhile, 2 has a significant cryogenic magnetocaloric effect with the maximum -Delta S-m of 26.73 at 3 K and 7 T, and 3 and 4 show interesting spin-glass behavior, which is rarely reported for Ln-containing complexes. Additionally, the solid-state photophysical properties of 1 and 3 display strong characteristic Eu3+ and Tb3+ photoluminescence emission in the visible region, indicating that Eu- and Tb-based luminescence are sensitized by the effective energy transfer from the ligand to the metal centers.