具有定向顺序和多边的奇拉流体膜
Lijie Ding1, Robert A Pelcovits1,2, Thomas R Powers1,2,3,4
1Department of Physics, Brown University, Providence, RI 02912, USA. Lijie_Ding@alumni.brown.edu.
Soft matter
|October 26, 2023
概括
蒙特卡洛模拟揭示了性液晶膜如何改变形状和内部秩序. 奇拉性驱动了从盘状到复杂形状的过渡,形成了不同的液晶相和π壁.
科学领域:
- 软物质物理学 软物质物理学
- 液晶物理学 液晶物理学
- 计算物理 计算物理
背景情况:
- 流体膜表现出复杂的行为,受曲阻力,边缘张力和方向顺序的影响.
- 螺旋相互作用和方向顺序和膜曲率之间的合可以导致异国情调的阶段和形态.
- 了解这些现象对于从细胞生物学到材料科学等领域至关重要.
研究的目的:
- 研究具有方向顺序和多边的流体膜的形状转换和出现的液晶相.
- 探索拉性和外部力量对膜形态和导演顺序的影响.
- 开发一个连续模型来解释观察到的行为.
主要方法:
- 蒙特卡洛模拟是在具有定义物理性质 (抗曲,边缘张力,倾斜合,性相互作用) 的流体膜上进行的.
- 模拟在没有和存在外部拉伸力的情况下进行.
- 为了解释模拟结果,我们构建了导演场的连续模型.
主要成果:
- 在没有外部力量的情况下,膜从盘状 (低力,性A阶段) 转变为具有胆固醇排序和π壁的状或三状 (高力) 形状.
- 在拉伸下,膜保持了圆柱形状,但根据倾斜合和性,表现出新的液晶相 (smectic-A,nematic, cholesteric).
- 模拟的π墙从倾斜墙转变为扭曲墙,因为性增加.
结论:
- 性是驱动显著形状变化和流体膜中复杂的导演排序的形成的关键因素.
- 外力可以稳定不同的液晶相,证明了机械应力和内部秩序之间的相互作用.
- 开发的连续模型为理解模拟的膜行为提供了一个理论框架.
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