Zhang Xiao-Jie, Sun Yu-Wei, Li Zhan-Wei, Sun Zhao-Yan
State Key Laboratory of Polymer Physics and Chemistry, Key Laboratory of Polymer Science and Technology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, China.
J Chem Phys. 2024 Aug 21;161(7). doi: 10.1063/5.0224224.
Guiding and dynamically modulating topological defects are critical challenges in defect engineering of liquid crystals. Here, we employ molecular dynamics simulations to investigate the transition dynamics and relative kinetic stability of defect patterns in two-dimensional nematic Gay-Berne liquid crystals confined within rectangular geometries. We observe the formation of various defect patterns including long-axis, diagonal, X-shaped, composite, and bend configurations under different confinement conditions. The competition between boundary effects and the uniformity of nematic orientation induces the continuous realignment of liquid crystal molecules, facilitating the spatially continuous transformation of defect patterns over time. This transition involves changes in both defect types and their locations, typically initiating from defect regions. Furthermore, we demonstrate that the relative stability of these defect patterns can be effectively controlled by adjusting confinement parameters and external field conditions. Our findings provide fundamental insights into the transition kinetics of defect patterns in confined nematic liquid crystals, thereby enhancing our ability to manipulate topological defects for advanced applications.
引导和动态调制拓扑缺陷是液晶缺陷工程中的关键挑战。在此，我们采用分子动力学模拟来研究限制在矩形几何结构内的二维向列型盖 - 伯恩液晶中缺陷图案的转变动力学和相对动力学稳定性。我们观察到在不同限制条件下形成了各种缺陷图案，包括长轴、对角线、X形、复合和弯曲构型。边界效应与向列取向均匀性之间的竞争导致液晶分子不断重新排列，促进了缺陷图案随时间在空间上的连续转变。这种转变涉及缺陷类型及其位置的变化，通常从缺陷区域开始。此外，我们证明了通过调整限制参数和外部场条件，可以有效地控制这些缺陷图案的相对稳定性。我们的研究结果为受限向列液晶中缺陷图案的转变动力学提供了基本见解，从而增强了我们为先进应用操纵拓扑缺陷的能力。
