Slow magnetic relaxation in Nd(<scp>iii</scp>) and Sm(<scp>iii</scp>) complexes formed in three-dimensional lanthanide-dicyanidometallate(<scp>i</scp>) frameworks exhibiting luminescent properties
Slow magnetic relaxation in Nd(<scp>iii</scp>) and Sm(<scp>iii</scp>) complexes formed in three-dimensional lanthanide-dicyanidometallate(<scp>i</scp>) frameworks exhibiting luminescent properties
复制标题
在三维镧系元素-二氰基金属酸盐 (<scp>i</scp>) 骨架中形成的 Nd(<scp>iii</scp>) 和 Sm(<scp>iii</scp>) 配合物中的慢磁弛豫表现出发光特性
DOI：
10.1039/d2tc04198g
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发表时间：
2023
影响因子：
6.4
通讯作者：
Ohkoshi Shin-ichi
中科院分区：
文献类型：
--
作者：
Kumar Kunal;Li Guanping;Stefanczyk Olaf;Chorazy Szymon;Nakabayashi Koji;Ohkoshi Shin-ichi
由不常见的Kramers离子（Nd（III）和Sm（III））组成的基于配位网络的磁体表现出发射性质，并且可以实现多种磁光应用。在本文中，我们表征了具有镧系离子与双氰双酸盐（I）在三维（3D）[LnIII（H2O）3][MI（CN）2]3（LnIII = Nd，Sm; MI = Ag，Au; NdAg，NdAu，SmAg和SmAu）配位聚合物中结晶的氰化物桥接的坚固网络。每个Ln III中心由六个氰基配体和三个水分子协调，导致三帽三角棱柱配位几何形状和单分子磁体（SMM）性质。交流磁研究证实存在一个缓慢的磁弛豫与计算的能量势垒为18.8，25.6，26.9，和22.3 K的NdAg，NdAu，SmAg，和SmAu，分别。为了了解中心Ln（III）离子的磁各向异性和对Kramers双重分裂的影响，进行从头计算，并探索Sm（III）-SMM的合适的磁各向异性以提高能垒。Nd（III）和Sm（III）离子的特征在于弱各向异性的磁性和易平面磁性字符，分别。此外，化合物显示可见光发射。含Nd（III）的框架显示来自[Ag（CN）2]n/[Au（CN）2]n中心的蓝色发射。SmAg和SmAu在冷却时显示多色发射，光致发光颜色范围从洋红色到蓝色，取决于温度。由于SmAu的发射强度急剧增加，其热敏能力也进行了研究。SmAu的最大相对热灵敏度为3.50%K −1（在80 K时），是3D框架中含Sm（III）的SMM中最高的。
Coordination network-based magnets composed of uncommon Kramers ions (Nd(III) and Sm(III)) exhibit emissive properties and may realize diverse magneto-optical applications. Herein we characterize cyanide-bridged robust networks possessing lanthanide ions combined with dicyanidometallates(I) crystallizing in three-dimensional (3D) [LnIII(H2O)3][MI(CN)2]3 (LnIII = Nd, Sm; MI = Ag, Au; NdAg, NdAu, SmAg, and SmAu) coordination polymers. Each LnIII centre is coordinated by six cyanido ligands and three water molecules, resulting in a tricapped trigonal prism coordination geometry and single-molecule magnet (SMM) properties. Alternating current magnetic studies confirm the presence of a slow magnetic relaxation with calculated energy barriers of 18.8, 25.6, 26.9, and 22.3 K for NdAg, NdAu, SmAg, and SmAu, respectively. To understand the magnetic anisotropy of the central Ln(III) ions and the effect on the Kramers doublet splitting, ab initio calculations are conducted and a suitable magnetic anisotropy for Sm(III)-SMMs is explored to enhance the energy barrier. The Nd(III) and Sm(III) ions are characterized by weakly anisotropic magnetic properties and an easy-plane magnetic character, respectively. Additionally, the compounds show visible emissions. The Nd(III)-containing frameworks exhibit bluish emissions from the [Ag(CN)2]n/[Au(CN)2]n centres. SmAg and SmAu display multi-coloured emissions upon cooling with the photoluminescence colours ranging from magenta to blue, depending on the temperature. Due to the sharp increase in the emission intensity for SmAu, its thermal sensing ability is also investigated. The maximum relative thermal sensitivity of 3.50% K−1 (at 80 K) for SmAu is the highest among Sm(III)-containing SMMs in a 3D framework.