在金属超分子聚合物中解脱并发包装多态性
Anja Langenstroer1, Kalathil K Kartha1, Yeray Dorca2
1Organisch-Chemisches Institut , Universität Münster , Corrensstraße 40 , 48149 Münster , Germany.
Journal of the American Chemical Society
|February 21, 2019
概括
这项研究揭示了一种 (II) 复合物,它形成了两个不同的稳定的超分子聚合物. 这些具有独特包装结构的多态体在室温下不会相互转化,
科学领域:
- 超分子化学
- 材料科学
- 协调化学
背景情况:
- 多态性在生物和自组系统中很常见.
- 超分子聚合物可以表现出与竞争的动力和热力学物种的通路复杂性.
- 短暂的动力物种通常寿命短,并迅速转化为热力学产物.
研究的目的:
- 研究一种能够形成稳定,具有竞争力的超分子聚合物的 π 结合的 Pt (II) 复合物.
- 阐明这些多形体的独特分子包装模式和稳定机制.
- 确定控制不同超分子物种的形成和稳定性的条件.
主要方法:
- 在非极性介质中自组合一个 π 结合的 Pt (II) 复合体.
- 使用实验技术和理论计算对高分子聚合物的表征.
- 通过相图和回火研究确定多态稳定性.
主要成果:
- Pt(II) 复合物自组成两种不同的超分子聚合物 (A:滑动,B:伪平行) 具有不同的包装.
- 多态体A和B表现出显著的稳定性,在室温下至少六个月没有相互转换.
- 非传统的N-H··Cl-Pt和N-H··O-相互作用分别稳定了多态A和B.
- 一个相位图精确地定义了两种物种的稳定性条件 (温度,度,冷却速度).
- 在高温回火时,多态A可以通过单体形成慢慢地转化为B.
结论:
- 这种系统在超分子聚合物中表现出稳定的并发多态,类似于晶体多态.
- 对自我组装条件的精确控制允许选择性形成和分离不同的超分子多态.
- 这些发现将晶体工程原理与超分子聚合结合,为设计功能性材料提供了新的途径.
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