使用光色水驱动液晶相位过渡
Mark J Moran1, Mitchell Magrini2, David M Walba2
1Department of Chemistry , Dartmouth College , Hanover , New Hampshire 03755 , United States.
Journal of the American Chemical Society
|October 9, 2018
概括
研究人员开发了一种用于液晶 (LC) 的新型合剂. 这种补充剂可实现光控制的自组装,从而产生可调光学特性和新的光门光学窗口.
科学领域:
- 软物质物理学
- 材料科学
- 有机化学
背景情况:
- 软物质的动态操纵是适应性功能材料的关键.
- 液晶 (LC) 显示基于其自组装的可调光物理性质.
- 对于先进的应用,控制LC与外部刺激的自组合至关重要.
研究的目的:
- 设计和合成一种新型的化剂,用于化液晶.
- 调查LC自组合和光物理性质的光诱导控制.
- 根据LCs中的光诱导相变演示一个光的光学窗口.
主要方法:
- 合成了一种新型的化剂,采用异化物支架和基于双的光开关.
- 用合成的性剂化液晶 (5CB).
- 使用特定波长的光 (例如蓝光) 来进行剂的光异构.
- 使用光学显微镜和光谱等技术进行LC相态度和光物理性质的表征.
主要成果:
- 合剂成功控制了阴性LC的自我组装和光物理特性.
- 光开关的双向性允许各种螺旋组件的动力捕获,反射不同的波长.
- 用蓝光照射诱导从胆固醇到质A*相的同热相过渡.
- 这种相位过渡可以调节LC膜的透明度,从而创建一个光门的光学窗口.
结论:
- 一种基于可光切换单元的新奇合剂可以精确控制LC的自组装和光学特性.
- 已证明的同热相过渡为光敏材料提供了一个新的机制.
- 开发的光门式光学窗户在自适应显示器和智能窗户中具有潜在的应用.
相关概念视频
Phase Transitions
23.2K
Whether solid, liquid, or gas, a substance's state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the solid pack closely together, generally in a pattern. The particles vibrate about their fixed positions but do not move or squeeze past their neighbors. In liquids, although the particles are closely spaced, they are randomly arranged. The position of the particles are not fixed—that is, they are free to move past their neighbors to...
23.2K
Phase Transitions: Sublimation and Deposition
20.2K
Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and standard pressure, a piece of dry ice (solid CO2) sublimes, appearing to gradually disappear without ever forming any liquid. Snow and ice sublimate at temperatures below the melting point of water, a slow process that may be accelerated by winds and the reduced atmospheric pressures at high altitudes. When solid iodine is warmed, the solid sublimes...
20.2K
Phase Transitions: Melting and Freezing
15.2K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
15.2K
Phase Transitions: Vaporization and Condensation
21.3K
The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. Vaporization occurs when the thermal motion of the molecules overcome the intermolecular forces, and the molecules (at the surface) escape into the gaseous state. When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules...
21.3K
M-Cdk Drives Transition Into Mitosis
6.6K
Checkpoints throughout the cell cycle serve as safeguards and gatekeepers, allowing the cell cycle to progress in favorable conditions and slow or halt it in problematic ones. This regulation is known as the cell cycle control system.
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
6.6K
Phase Diagrams
50.2K
A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. These diagrams indicate the physical states that exist under specific conditions of pressure and temperature and also provide the pressure dependence of the phase-transition temperatures (melting points, sublimation points, boiling points). Regions or areas labeled solid, liquid, and gas represent single phases, while lines or curves represent...
50.2K


