Yang Yang, Laird Brian B
Department of Materials Science and Engineering, University of California, Berkeley , Berkeley, California 94720, United States.
J Phys Chem B. 2014 Jul 17;118(28):8373-80. doi: 10.1021/jp5019313. Epub 2014 Apr 22.
We examine the thermodynamics and intrinsic structure of the Al-Pb liquid-liquid interface using molecular dynamics simulation and embedded atom method potentials. The instantaneous interfacial positions, from which the intrinsic structure and the capillary fluctuation spectrum are determined, are calculated using a grid-based method. The interfacial free energy extracted from the capillary fluctuation spectrum is shown to be in excellent agreement with that calculated mechanically by integrating the stress profile. The intrinsic liquid-liquid interfacial density profile shows structural oscillations in the liquid phases in the interfacial region that are shown to be quantitatively similar to the radial distribution functions of the bulk liquid, consistent with theoretical predictions from classical density functional theory and with earlier simulations on liquid-liquid and liquid-vapor interfaces. In addition, we show the mean interfacial density profile for this system is well described as a convolution of the intrinsic density profile and the probability distribution of interfacial position.
我们使用分子动力学模拟和嵌入原子方法势来研究铝-铅液-液界面的热力学和本征结构。通过基于网格的方法计算出瞬时界面位置，据此确定本征结构和毛细管涨落谱。从毛细管涨落谱中提取的界面自由能与通过对应力分布进行积分机械计算得到的结果高度吻合。本征液-液界面密度分布在界面区域的液相中呈现出结构振荡，这些振荡在定量上与体相液体的径向分布函数相似，这与经典密度泛函理论的理论预测以及早期关于液-液和液-气界面的模拟结果一致。此外，我们表明该系统的平均界面密度分布可以很好地描述为本征密度分布与界面位置概率分布的卷积。
