在难以捉摸的-splay和splay-bend弹性常数上,有毒液晶的液晶晶体
Davide Revignas1, Alberta Ferrarini1
1Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy.
The Journal of chemical physics
|July 20, 2023
概括
这项研究提供了微观估计的挑战性弹性常数在内马体液晶,揭示,子-splay (K24) 是显著的和splay-bend (K13) 对于理论一致性至关重要.
科学领域:
- 软物质物理学 软物质物理学
- 液晶理论 液晶理论
- 材料科学 材料科学 材料科学
背景情况:
- 阴性液晶弹性通常是使用散装变形模式建模的:splay,twist和 bend.
- 额外的弹性术语, Saddle-splay (K24) 和 Splay-bend (K13),在封闭系统中具有重要意义,但在实验和理论上很难确定.
- 以前的理论质疑了为K24和K13获得明确显微表达式的可能性.
研究的目的:
- 在各种导体变形下,获得硬棒磁体的变形自由能量密度的微观估计.
- 为了获得棒状内马特的所有弹性系数的闭式显微表达式.
- 调查弹性常数的相对大小和K13对理论一致性的重要性.
主要方法:
- 利用Parsons-Lee校正的Onsager理论来建模硬棒带状物.
- 对不同导体变形的变形自由能量密度进行微观估计.
- 微观结果与宏观弹性自由能量密度在缓慢变化的导体极限中进行了比较.
主要成果:
- 导出了杆状内马特的所有弹性系数的综合微观表达式.
- 发现,在各种粒子长度和密度上,坐-散裂常数 (K24) 始终大于K11和K22.
- 证明了曲贡献 (K13) 对微观变形自由能量计算的一致性至关重要.
结论:
- 该研究成功地为尼马系统中难以捉摸的弹性常数 (K24和K13) 提供了理论显微表达式.
- 这些发现突出了-splay和splay-bend弹性在内马特行为中的重要作用,特别是在局限的几何结构中.
- 这项工作推进了对液晶弹性的理论理解,为未来的实验验证提供了基础.
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