Shao Mingzhe, Wang Jianjun, Zhou Xin
Institute of Chemistry, Chinese Academy of Science, Beijing 100190.
School of Physics, University of Chinese Academy of Sciences, Beijing 100049.
Sci Rep. 2015 Apr 2;5:9491. doi: 10.1038/srep09491.
Line tension of three-phase contact lines is an important physical quantity in understanding many physical processes such as heterogeneous nucleation, soft lithography and behaviours in biomembrane, such as budding, fission and fusion. Although the concept of line tension was proposed as the excess free energy in three-phase coexistence regions a century ago, its microscopic origin is subtle and achieves long-term concerns. In this paper, we correlate line tension with anisotropy of diagonal components of stress tensor and give a general formula of line tension. By performing molecular dynamic simulations, we illustrate the formula proposed in Lennard-Jones gas/liquid/liquid and gas/liquid/solid systems, and find that the spatial distribution of line tension can be well revealed when the local distribution of stress tensor is considered.
三相接触线的线张力是理解许多物理过程（如异质成核、软光刻以及生物膜中的行为，如出芽、裂变和融合）的一个重要物理量。尽管线张力的概念在一个世纪前就被提出作为三相共存区域中的过剩自由能，但其微观起源很微妙，长期以来一直备受关注。在本文中，我们将线张力与应力张量对角分量的各向异性相关联，并给出了线张力的通用公式。通过进行分子动力学模拟，我们在 Lennard-Jones 气/液/液和气/液/固系统中对所提出的公式进行了说明，并且发现当考虑应力张量的局部分布时，线张力的空间分布能够得到很好的揭示。
