具有二维结合层相的铁电胺替代衍生物
Hayato Anetai1, Takashi Takeda1,2, Norihisa Hoshino1,2
1Graduate School of Engineering , Tohoku University , Sendai 980-8579 , Japan.
Journal of the American Chemical Society
|January 17, 2019
概括
胺衍生物呈现铁电液晶相. 层状相中的二维结网络显示出比一维柱状相显著更高的残余极化.
科学领域:
- 材料科学
- 有机化学
- 晶体学
背景情况:
- 基胺替代的和衍生物呈现盘状六角柱状液晶相.
- 这些阶段的特点是单维 (1D) 分子间N-H·O结合.
- 这种结的方向可以通过交流电压逆转,从而产生铁电性质.
研究的目的:
- 研究带有胺链的新型非π平面烯衍生物的铁电性质.
- 为了比较液晶行为和光学活性衍生物的铁电性.
- 阐明分子结构,结网络和铁电反应之间的关系.
主要方法:
- 合成基胺替代的,和衍生物.
- 使用极化光学显微镜和差分扫描热量计等技术对液晶相进行表征.
- 通过测量极化电场 (P-E) 歇斯底里循环来研究铁电性质.
- 使用X射线衍射和其他结构方法分析分子组合和结网络.
主要成果:
- 和衍生物表现出1D柱状液晶相与铁电P-E歇斯底里.
- 拉塞米衍生物呈现双层层状液晶相 (330-420 K),具有二维结合和铁电性.
- 由于分子组合的改变,光学活性衍生物没有表现出液晶性.
- 与1D柱状相相比,状相显示了显著更高的残余极化 (11.1μC cm-2).
结论:
- 用胺替代的烯衍生物可以形成铁电液晶相.
- 双维结网络在层状阶段促进比1D系统更强的铁电反应.
- 分子组合和结网络密度对于实现高铁电性能至关重要.
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