一个硬体排斥驱动的合堆:在晶体固体中相关的分子旋转和热敏转速
Mingoo Jin1, Ryunosuke Kitsu2, Natsumi Hammyo2
1Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, Hokkaido 060-8628, Japan.
Journal of the American Chemical Society
|December 7, 2023
概括
新开发的三三旋转器形成具有独特相关分子运动的柱状结构. 这些运动可以通过温度诱导的相位过渡进行切换,提供分子级别的变速控制.
科学领域:
- 超分子化学
- 材料科学
- 固态化学
背景情况:
- 三酸衍生物在分子机器中的潜力是众所周知的.
- 在固态中控制分子运动仍然是一个重大挑战.
- 设计具有可预测和可切换动态特性的材料对于先进的应用至关重要.
研究的目的:
- 开发一种新型的三三旋转器,
- 研究这些旋转器的晶体结构和分子动力学.
- 通过热诱导的相变来控制分子运动的可能性.
主要方法:
- 一个新的三三旋转器的合成,
- 可变温度固态2H核磁共振光谱
- 分析晶体结构和相变的X射线衍射研究.
主要成果:
- 在晶体阶段形成柱状堆叠的离合结构.
- 观察两个不同的,相互可转换的相关分子运动 (翻动和180°旋转).
- 通过热诱导的晶体到晶体相位过渡实现的运动之间的切换.
- 与两个旋转运动相关的负变化.
结论:
- 巨大的稳定器的硬体排斥驱动分子间堆叠和相关运动.
- 热诱导的相位过渡提供了对分子旋转的可逆控制.
- 这种策略为设计具有可调节分子动力学和变速功能的材料提供了有前途的途径.
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