复杂的多色和四色性液晶中的关键现象
Xiangbing Zeng1, Robert Kieffer, Benjamin Glettner
1Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK.
概括
将不兼容的侧链添加到T形分子中,会产生具有多个细胞组成的复杂液晶蜂巢. 观察到相隔和混合蜂巢相之间的可逆过渡,类似于磁性过渡.
科学领域:
- 材料科学 材料科学 材料科学
- 软物质物理学 软物质物理学
- 晶体学 晶体学是指结晶学.
背景情况:
- T形分子形成液晶蜂巢,具有芳香核心和柔性侧链.
- 这些结构呈现出芳香的细胞壁和侧链填充的内部.
- 以前的研究集中在更简单的分子架构上.
研究的目的:
- 研究将第二个不兼容的侧链 (X形分子) 添加到T形液晶系统的影响.
- 探索复杂的形图案的形成和不同的细胞组成.
- 描述观察到的热可逆相变的特征.
主要方法:
- 合成和表征T形和X形分子.
- 使用显微镜和热方法进行液晶相态行为分析.
- 蜂巢模式和细胞组成的结构分析.
主要成果:
- 添加X形分子诱导了复杂的蜂巢,最多有五种不同的细胞组成 ("颜色") 和多角形状.
- 不兼容的侧链之间的几何挫折阻止了清洁相位分离,导致了复杂性.
- 在多色 (分相) 和单色 (混合) 蜂阶段之间观察到一个热可逆的过渡.
结论:
- 液晶中不兼容的侧链可以导致复杂的自我组装结构,出现复杂性.
- 观察到的相位过渡类似于磁系统中的库里过渡,由分子重定向驱动.
- 这项工作扩大了对软物质和挫败系统自我组装的理解.
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