液晶对齐的表面双极控制
Jeffrey J Schwartz1,2, Alexandra M Mendoza1,3, Natcha Wattanatorn1,3
1California NanoSystems Institute, University of California, Los Angeles , Los Angeles, California 90095, United States.
Journal of the American Chemical Society
|April 20, 2016
概括
在纳米尺度上控制分子组合需要理解分子间的力量. 这项研究揭示了自组合单层中的分子二极体如何决定液晶对齐,从而实现精确的纳米级工程.
科学领域:
- 纳米科学与工程
- 材料科学
- 表面化学
背景情况:
- 对分子组合的精确控制对于工程纳米结构和功能至关重要.
- 液晶组件对表面特性非常敏感,将纳米级相互作用转化为宏观光学信号.
- 自组装单层 (SAM) 有效地修改表面相互作用并影响LC对齐.
研究的目的:
- 从分子几何学,倾斜和顺序等其他因素中解脱SAM-LC双极合的影响.
- 调查不同二极体大小和方向的碳乙醇和 - 乙醇定位异构体如何影响LC对齐.
- 通过理解二极合来推进纳米级分子相互作用的工程.
主要方法:
- 作为SAM,使用了具有不同双极特性的碳乙醇和 - - 乙醇定位异构体.
- 用这些不同的SAM作为对齐层制造的LC细胞.
- 测量LC导向和定能量以探测SAM-LC相互作用.
主要成果:
- 在SAM中分子双极的正常组件决定了在平面中的LC导向.
- LC对齐作为一个敏感的探测器来量化SAM-LC相互作用的强度.
- 证明了分子单层与其环境之间的双极合在确定分子方向方面的关键作用.
结论:
- 在SAM中分子双极的方向是控制LC对齐的关键因素.
- 这项工作提供了一种利用双极合来设计纳米级分子相互作用的方法.
- 这些发现使得更复杂的材料设计具有量身定制的纳米特征.
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