在固态中旋转一个重的三烯:朝着工程纳米级的人工分子机器的方向
Xing Jiang1, Braulio Rodríguez-Molina, Narega Nazarian
1Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095-1569, United States.
Journal of the American Chemical Society
|June 10, 2014
概括
这项研究介绍了一种新型的固态分子旋转器,采用大型三旋转器. 尽管增加了固体阻碍,但旋转器在固体状态下实现了快速运动,证明了高效的分子动力学.
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
- 化学物理 化学物理
背景情况:
- 分子旋转器对于开发先进的功能材料至关重要.
- 以前的固态分子转子使用较小的烯单元.
- 较大的旋转器,如三角形旋转器,由于增加的范德瓦尔斯力和固态阻碍,面临着挑战.
研究的目的:
- 设计和描述一个固态分子旋转器与一个重的三旋转器.
- 为了研究三基旋转器在固态中的动力学和旋转屏障.
- 为了克服硬体挑战,使用一个刚性,树突式定位器.
主要方法:
- 一个分子旋转器的合成,其中包括一个三基单元和一个树突式定位器.
- 可变温度固态核磁共振光谱 ((2) H NMR) 来探测分子运动.
- 对旋转潜力和动态的分析.
主要成果:
- 成功设计和合成一个固态分子旋转器与三旋转器.
- 确定一个对称的三倍旋转电位,其屏障为10.2 kcal/mol.
- 快速旋转动态的量化 (大约) 4600布朗的跳跃/秒在300K) 尽管旋转器的大小.
结论:
- 这项研究证明了使用大型三烯单元实现高效的固态分子旋转的可行性.
- 刚性树突状态器有效地减轻了硬体障碍,使得分子动力学得到控制.
- 这项工作推进了固态分子机器和功能材料的设计原则.
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