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基于粒子和连续的模型,用于两个维度的封闭内马蒂克.
Humberto Híjar1, Apala Majumdar2
1Research Center, La Salle University Mexico, Mexico. humberto.hijar@lasalle.mx.
Soft matter
|April 17, 2024
概括
我们使用基于粒子的方法在多边形中模拟了封闭的液晶. 结果与连续性理论一致,揭示了多边形的大小如何影响缺陷动态和放松.
科学领域:
- 软物质物理学 软物质物理学
- 计算材料科学科学 计算材料科学
背景情况:
- 当被限制在几何形状中时,阴性液晶表现出独特的特性.
- 了解它们的行为需要桥接基于粒子和连续的模拟方法.
研究的目的:
- 使用N-MPCD算法模拟和分析2D多边形内封闭的阴性液晶.
- 为了比较基于粒子的N-MPCD模拟与连续性的兰道-德热内斯理论.
- 为了研究多边形大小和内马性对液晶行为和缺陷动态的影响.
主要方法:
- 使用基于粒子的随机多粒子碰撞动态 (N-MPCD) 算法.
- 在正规的二维多边形 (正方形,五角形,六角形) 中封闭的模拟阴性液晶.
- 使用关闭参数来将N-MPCD参数映射到Landau-de Gennes框架中.
主要成果:
- 对于较大的多边形,N-MPCD的平均配置与Landau-de Gennes理论一致.
- 在N-MPCD中,放松动态显示了类似于兰道-德热内斯点的动力陷.
- 在N-MPCD中,有限尺寸效应会减慢速度,并吸引多边形顶点的内马特缺陷.
结论:
- 该研究提供了基于粒子 (N-MPCD) 和连续性 (Landau-de Gennes) 方法之间的综合比较,用于受限的阴性学.
- N-MPCD模拟验证了连续性理论的预测,并提供了对纳米尺度现象的见解.
- 这些发现对于开发软物质物理学中先进的多尺度理论至关重要.
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