玻璃般的放松在德弗里斯的粘液液晶中,由曲核心分子组成
Vishnu Deo Mishra1, G Pratap2, Arun Roy1
1Soft Condensed Matter Group, Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560080, India.
Physical review. E
|March 16, 2024
概括
这项研究研究了一种基于烯的新型曲核液晶. 它在低温下表现出德弗里斯SmA阶段和独特的玻璃状行为,与典型的液晶不同.
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
- 有机化学 有机化学
背景情况:
- 曲核心液晶由于其分子几何学而具有独特的特性.
- 德弗里斯SmA阶段是一种罕见的液晶阶段,其特点是层的收缩最小.
- 了解液晶的低温行为对于其应用至关重要.
研究的目的:
- 为了实验性地研究基于蒂奥芬的Achiral曲核心分子的液晶性质.
- 描述相变的特征,特别是德弗里斯SmA相和低温行为.
- 探索介电性质并了解玻璃过渡机制.
主要方法:
- 合成和表征基于蒂奥芬的阿基拉尔曲核分子.
- 差分扫描热量计 (DSC) 用于相位过渡分析.
- 介电光谱学用于研究放松动态和玻璃性行为.
主要成果:
- 该化合物表现出一个相序列:异构,尼马特 (N),德弗里斯斯斯麦克特A (SmA) 和斯麦克特C (SmC).
- 在SmA到SmC过渡期间没有观察到显著的层收缩,这证实了SmA阶段的德弗里斯性质.
- SmC 阶段在 271 K 呈现玻璃过渡,介电光谱检测显示了按照 Vogel-Fulcher-Tammann 方程的 Cole-Cole 类型的放松模式,表明脆弱的玻璃性行为.
结论:
- 发现了一种新型的曲心液晶,表现出德弗里斯SmA阶段.
- 该材料在低温下表现出不寻常的玻璃状行为,与典型的液晶结晶异常.
- 这些发现有助于理解曲芯液晶中的结构-性质关系及其独特应用的潜力.
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