在液晶混合物中,部分失序的晶体相和玻璃状的粘性相
Aleksandra Deptuch1, Anna Drzewicz1, Magdalena Urbańska2
1Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, PL-31342 Kraków, Poland.
Materials (Basel, Switzerland)
|July 12, 2025
概括
这项研究研究了液晶混合物,揭示了相变和玻璃化. 添加3F5FPhF6影响了 smectic 阶段和结晶行为,介电光谱分析了放松动态.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 物理化学 物理化学
背景情况:
- 液晶表现出不同的中相,这对于先进材料至关重要.
- 了解液晶混合物中的相变和玻璃形成对于开发新的功能性材料至关重要.
- 液晶中的分子结构和宏观性质之间的相互作用仍然是活跃的研究领域.
研究的目的:
- 为了研究MHPOBC和3F5FPhF6混合物的相位行为.
- 分析不同摩尔比对形A*,C*和CA*阶段形成的影响.
- 研究这些混合物的玻璃化和结晶现象,并描述它们的放松动态.
主要方法:
- 准备和研究三种液晶混合物 (MIX5FF6-1,MIX5FF6-2,MIX5FF6-3) 的MHPOBC和3F5FPhF6.6的摩尔比率不同.
- 液晶相的观测使用[如果有,请提及技术,否则省略].
- 宽带介电光谱学用于研究涂层和晶体阶段的放松时间.
主要成果:
- 所有混合物都表现出性A*,性C*和性CA*阶段.
- 在纯MHPOBC中存在的六次性XA*阶段随着3F5FPhF6度的增加而消失.
- 在等等质混合物中观察到质CA*的玻璃化,其玻璃过渡温度和脆性指数与纯3F5FPhF6.6相比.
- 在冷却后,在含有较低3F5FPhF6分数的混合物中,发生了部分结晶到无序的晶相.
结论:
- 添加3F5FPhF6显著改变了MHPOBC的相位行为,抑制了六次性XA*相位,并促进了玻璃化.
- 介电光谱学揭示了在超冷却的状XA*和状CA*阶段的明显放松动态,使用已建立的模型进行分析.
- 该研究提供了对二元液晶系统的结构-性质关系的见解,这与设计具有量身定制的热和介电性质的材料有关.
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