在自我组织的螺旋式上层结构中,光驱动的可逆手性反转
Manoj Mathews1, Rafael S Zola, Shawn Hurley
1Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, Ohio 44242, USA.
Journal of the American Chemical Society
|December 4, 2010
概括
研究人员通过使用光响应性性剂,在液晶中实现了可逆色调. 这种快速光子模式切换使可调节的反射颜色从蓝色到近红外,具有新型光学材料的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
- 光子学 是一个光子学.
背景情况:
- 胆固醇液晶表现出自我组织的螺旋式超结构.
- 状剂诱导和控制液晶中的螺旋结构.
- 光异构化分子具有可调光的特性.
研究的目的:
- 开发一种快速光子模式方法,用于可逆的手性反转在胆固醇液晶中.
- 为了利用可光异构化性循环亚烯烯作为可调节光学性质的剂.
- 为了研究使用不同的剂切换状态来诱导相反的螺旋手性.
主要方法:
- 合成和表征两个性循环亚二.
- 添加剂的融入到无形液晶宿主中.
- 通过光照射诱导的光异构化 (trans-cis).
- 使用一种新的方法直接确定螺旋手形.
主要成果:
- 合性补充剂表现出可逆的跨cis异体化,没有种族化.
- 观察到高螺旋扭力和显著的光异构化诱导的变化.
- 实现了从蓝色到近红外的反射颜色的可逆调整.
- 相反的螺旋手性是由多剂的不同切换状态引起的.
结论:
- 可光异构化性循环剂能够在胆固醇液晶中实现快速,可逆的手性反转.
- 在广泛的光谱 (从蓝色到近红外) 中,光感应色调是可行的.
- 开发的方法允许在长胆固醇相中明确确定螺旋手性.
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