Physics of liquid crystals of bent-shaped molecules
Physics of liquid crystals of bent-shaped molecules
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DOI：
10.1103/revmodphys.90.045004
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发表时间：
2018-11-20
影响因子：
44.1
通讯作者：
Selinger, Jonathan V.
中科院分区：
文献类型：
--
作者：
Jakli, Antal;Lavrentovich, Oleg D.;Selinger, Jonathan V.
热致液晶可以由各种分子形状形成，其中一些在125年前被发现。最简单和研究最多的液晶是由棒状分子组成的，并导致了今天无处不在的液晶显示器。虽然应用科学家和工程师一直在完善液晶显示器，但一大群液晶科学家对香蕉形（香蕉形）分子的液晶感到兴奋。这些化合物在20年前首次被报道，从那时起就成为当前液晶科学的中心。“香蕉狂热”是因为即使是分子形状中的一个小扭结也会导致新的性质和相。这篇综述总结了各种各样的新结构和物理性质，并描述了基本的物理。宏观性质的依赖性上的分子的形状和灵活性的中心核心的强调。大多数刚性的α-核分子形成近晶结构，有时是柱状结构;只有少数形成α-相。相比之下，大多数柔性的α-核分子形成纳米结构的α-相，包括最近发现的扭曲-弯曲α-相。
Thermotropic liquid crystals can be formed by various molecular shapes, some discovered over 125 years ago. The simplest and most-studied liquid crystals are made of rod-shaped molecules and led to today's omnipresent liquid crystal displays. While applied scientists and engineers have been perfecting liquid crystal displays, a large group of liquid crystal scientists have become excited about liquid crystals of bent-shaped (banana-shaped) molecules. These compounds were first reported 20 years ago and since then have taken center stage in current liquid crystal science. The "banana mania" is due to the fact that even a small kink in the molecular shape leads to fundamentally new properties and phases. This review summarizes the large variety of novel structures and physical properties and describes the underlying physics. The dependence of macroscopic properties on both the shape of the molecules and the flexibility of the central core is emphasized. Most rigid bent-core molecules form smectic and sometimes columnar structures; only a minority forms nematic phases. By contrast, most flexible bent-core molecules form nanostructured nematic phases, including the twist-bend nematic phase discovered very recently.