Monderkamp Paul A, Wittmann René, Te Vrugt Michael, Voigt Axel, Wittkowski Raphael, Löwen Hartmut
Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
Institut für Theoretische Physik, Center for Soft Nanoscience, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany.
Phys Chem Chem Phys. 2022 Jul 6;24(26):15691-15704. doi: 10.1039/d2cp00060a.
Observing and characterizing the complex ordering phenomena of liquid crystals subjected to external constraints constitutes an ongoing challenge for chemists and physicists alike. To elucidate the delicate balance appearing when the intrinsic positional order of smectic liquid crystals comes into play, we perform Monte-Carlo simulations of rod-like particles in a range of cavities with a cylindrical symmetry. Based on recent insights into the topology of smectic orientational grain boundaries in two dimensions, we analyze the emerging three-dimensional defect structures from the perspective of tetratic symmetry. Using an appropriate three-dimensional tetratic order parameter constructed from the Steinhardt order parameters, we show that those grain boundaries can be interpreted as a pair of tetratic disclination lines that are located on the edges of the nematic domain boundary. Thereby, we shed light on the fine structure of grain boundaries in three-dimensional confined smectics.
观察和表征受外部约束的液晶的复杂有序现象，对化学家和物理学家来说都是一项持续的挑战。为了阐明近晶型液晶的固有位置有序发挥作用时出现的微妙平衡，我们对具有圆柱对称性的一系列空腔中的棒状粒子进行了蒙特卡罗模拟。基于对二维近晶取向晶界拓扑结构的最新见解，我们从四方对称性的角度分析了新出现的三维缺陷结构。使用由施泰因哈特序参量构建的合适的三维四方序参量，我们表明这些晶界可以解释为位于向列畴边界边缘的一对四方位错线。由此，我们揭示了三维受限近晶中的晶界精细结构。
