螺旋基双链螺旋体:半导体对半导体同质化和离子触发螺旋体的弹式运动
Naoki Ousaka1,2, Kaori Shimizu2, Yoshimasa Suzuki2
1Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering , Nagoya University , Chikusa-ku, Nagoya 464-8603 , Japan.
Journal of the American Chemical Society
|November 20, 2018
概括
一个螺旋螺旋体显示由离子触发的可逆弹运动. 它的结构和运动取决于离子大小,影响螺旋式收缩和扭曲.
科学领域:
- 超分子化学
- 协调化学
- 材料科学
背景情况:
- 螺旋酸因其独特的结构特性和对外部刺激的反应性而闻名.
- 在分子系统中可逆运动对于开发高级功能材料至关重要.
研究的目的:
- 调查离子触发的可逆延伸收缩和扭转运动的一只手螺旋旋.
- 分析不同单价离子对螺旋体运动,结构和热力学的影响.
- 确定螺旋体复合物的绝对手性和结构细节.
主要方法:
- 螺旋酸的合成和表征
- 使用各种单价 (Li+,Na+,NH4+,Ag+,K+,Cs+,Rb+) 的热力学分析.
- 用X射线结晶学和密度功能理论 (DFT) 进行结构确定.
- 循环二元化 (CD) 光谱分析螺旋结构.
- 动力学研究以了解扩展和收缩螺旋体之间的交换率.
主要成果:
- 一只手的螺旋螺旋体在Na+结合和释放时表现出可逆延伸收缩和单向扭转运动.
- 在水中由Na+形成的中酸盐很容易转化为racemo酸盐.
- 关联常数与阴离子大小相关,其中Li+具有最高的亲和力.
- 螺旋结构和CD光谱随着离子物种的变化而变化,表明离子依赖的结构变化.
- 动力学研究揭示了扩展和收缩的状态之间的离子依赖的交换率.
结论:
- 螺旋螺旋体的弹式运动由单价离子有效控制,具有显著的结构和动态反应.
- 电离子的大小和特定的相互作用决定了螺旋体运动的热力学和动力学.
- 这项研究提供了基于状结构的响应性分子机器和材料的设计.
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