由化溶剂介导的阿基拉尔单体组装的超分子聚合物中的旋转过
Amit Kumar Mondal1, Marco D Preuss2, Marcin L Ślęczkowski2
1Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Journal of the American Chemical Society
|April 30, 2021
概括
在由奇拉溶剂诱导的由奇拉单体制成的聚合物中观察到奇拉诱导的旋转选择性 (CISS). 这表明CISS可以来自于超分子性,而不仅仅是分子性.
科学领域:
- 材料科学
- 凝聚物质物理学
- 超分子化学
背景情况:
- 此前已在由具有立体中心的同体基质构成的聚合物和超分子结构中观察到性诱导旋转选择性 (CISS) 效应.
- 对于观察CISS效应而言,需要使用奇拉基质构件是该领域的一个关键问题.
研究的目的:
- 为了研究在多大程度上需要性构建块来表现性诱导自旋选择性 (CISS) 效应.
- 为了证明CISS效应的超分子聚合物构建完全由achiral单体.
主要方法:
- 使用阿基拉单体制造超分子聚合物.
- 使用奇拉溶剂诱导超分子性,然后除去溶剂.
- 对聚合物纤维轴垂直的自旋选择性电子传输的测量.
- 旋转极化与循环二极化 (CD) 光谱的相关性.
- 对旋转偏振的厚度依赖性的分析.
- 旋转偏振的温度依赖性研究.
主要成果:
- 在仅由阿基拉单体组成的高分子聚合物中成功证明了CISS效应.
- 由短暂暴露于奇拉溶剂引起的超分子性足以引起旋转选择性传输.
- 对于垂直于纤维轴的电子传输,观察到旋转极化,与CD光谱强度相关,表明非局部效应.
- 随着样本厚度的增加,旋转极化增加,这归因于CISS效应和分散机制之间的相互作用.
- 温度依赖性研究提供了声子对自旋偏振的理论贡献的证据.
结论:
- 基拉尔诱导的自旋选择性 (CISS) 不仅限于具有固有的分子基拉力系统; 超分子基拉力也可以诱导这种效应.
- 这些系统中的CISS效应是非局部的,受样本厚度和温度依赖的散射机制的影响.
- 这项工作为理论模型提供了实验支持,表明声子参与了CISS效应.
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