超分子弹式Fe(II) 旋转交叉复合体经历两种不同的温度调节的巨型和无otropic热膨胀
Xin-Hua Zhao1, Yi-Fei Deng1, Jing Xi1
1Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, P. R. China.
Angewandte Chemie (International ed. in English)
|November 6, 2024
概括
这项研究介绍了一种新的铁(II) 旋转交叉 (SCO) 复合体,该复合体表现出巨大的,异构的"呼吸"运动. 这种动态材料结合了SCO和类似弹的性能,用于先进的应用.
科学领域:
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
- 协调化学 协调化学
背景情况:
- 响应刺激的动态分子是智能材料的关键.
- 超分子弹和旋转交叉 (SCO) 复合体表现出随着外部触发的宏观变化.
- 在单个分子中集成多个动态功能是一个重大挑战.
研究的目的:
- 为了合成和表征一个独特的三核Fe (II) -SCO复合体,具有可调节的特性.
- 研究SCO的协同效应,联结体旋转和金属对金属相互作用对分子行为的作用.
- 探索创造多功能动态材料的潜力.
主要方法:
- 合成一种的三核Fe(II) -SCO复合体, [(R-L) FeII{Au(CN) 2}2] (R 1),具有可旋转的环.
- 通过Au-Au接触形成的21-螺旋式超分子链的结构分析.
- 测量磁力和热膨胀以研究过渡和动态反应.
主要成果:
- 该综合体表现出两个歇斯底里磁过渡:一个非旋转过渡 (360380 K) 和一个SCO过渡 (160280 K) 与对称性破坏 (P212121P21).
- 环旋转 (向内/向外) 伴随着这两种磁性过渡.
- 观察到螺旋链的可逆,巨型和异型弹式运动,螺旋链的斜率随温度显著变化.
结论:
- 这项研究成功地将自旋交叉行为与超分子弹式运动在单个Fe (II) 复合体中集成.
- 观察到的巨型和异型热膨胀 ("呼吸") 强调了多种动态因素的协同作用.
- 这项工作为设计先进的多功能动态材料为未来的技术应用提供了基础.
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