Division of Molecular and Materials Simulation, State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China.
Sci Rep. 2013;3:2008. doi: 10.1038/srep02008.
In this work, we present a theoretical method to determine the line tension of nanodroplets on homogeneous substrates via decomposing the grand free energy into volume, interface and line contributions. With the obtained line tension, we check the viability of Young equation and find that the chemical potential dependence (or equivalently, droplet curvature dependence) of the interface tensions is crucial for the viability of modified Young equation at the nanometer scale. In particular, the linear relationship between the cosine of contact angle and the curvature of the contact line, which is often used to determine the line tension, is found to be incorrect at the nanometer scale.
在这项工作中，我们提出了一种理论方法，通过将总自由能分解为体积、界面和线贡献来确定纳米液滴在均匀基底上的表面张力。利用得到的表面张力，我们检验了修正 Young 方程的可行性，发现界面张力的化学势依赖性（或者等效地，液滴曲率依赖性）对于在纳米尺度上修正 Young 方程的可行性至关重要。特别是，通常用于确定表面张力的接触角余弦与接触线曲率之间的线性关系，在纳米尺度上被发现是不正确的。
