通过防止分子间结,削弱一维中的链间相互作用 (II) 协调聚合物
Michał Rams1, Thomas Lohmiller2, Michael Böhme3
1M. Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Kraków, Poland.
Inorganic chemistry
|June 15, 2023
概括
该研究合成了一种新的化合物[Co(NCS) 2 ((N-甲基氨) 2 (1),发现其磁性特性与类似的氨化合物 (2) 有显著差异. 在化合物1中消除键减弱了链间相互作用,降低了磁性排序温度.
科学领域:
- 协调化学 协调化学
- 磁电化学 磁电化学 磁电化学
- 固态物理 固态物理
背景情况:
- (II) 硫酸复合物与氨基联结物形成延长链结构.
- 分子间相互作用,如键,显著影响协调聚合物的磁性.
- 了解结构属性关系对于设计磁性材料至关重要.
研究的目的:
- 为了合成和表征一种新的 ((II) 硫酸酸复合物与N-甲基氨.
- 为了研究合成化合物的磁性和磁性异构性.
- 为了比较磁性行为和分子间相互作用与相关的氨酸复合物.
主要方法:
- 合成[Co(NCS) 2 ((N-甲基兰) 2) (1) 通过Co(NCS) 2与N-甲基兰的反应.
- 单晶X射线衍射以确定晶体结构和协调环境.
- 磁感应度测量和远至远红外 - - 里叶变换 - - 特拉赫兹 - - 电子偏磁共振 (FD-FT THz-EPR) 光谱仪用于磁性表征.
主要成果:
- 化合物1具有八面体协调的(II) 离子在线性链中,由酸离子连接在一起,缺少氨酸类型中存在的链际键 (2).
- 计算研究和光谱学揭示,化合物1比化合物2具有较低的轻轴异质性,具有类似的轻轴方向.
- 磁性测量表明,与化合物2相比,化合物1中的磁性排序的临界温度显著较低,这归因于链间相互作用减弱.
结论:
- 在[Co(NCS) 2 ((N-甲基氨) 2) (1) 中缺少N-H···S结,导致相比[Co(NCS) 2 ((aniline) ] (2) 中,链间相互作用能量减少了9倍.
- 这种链间相互作用的减弱显著降低了化合物1中磁性排序的临界温度.
- 这项研究强调了分子间键在调解 ((II) 硫酸) 链化合物中链间磁性合中的关键作用.
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