Molecular Dynamics Simulation of Heterogeneous Nucleation and Growth of Argon at Polyethylene Films
Molecular Dynamics Simulation of Heterogeneous Nucleation and Growth of Argon at Polyethylene Films
复制标题
DOI：
10.1021/jp073713d
复制
发表时间：
2007-10
影响因子：
3.7
通讯作者：
R. Rozas;T. Kraska
中科院分区：
文献类型：
--
作者：
R. Rozas;T. Kraska
用分子动力学模拟方法研究了过饱和Ar蒸气在聚乙烯表面的非均相成核与生长。对于高含湿性系统，选择特定的系统作为模型。模拟是在非平衡系综下进行的，其中包括冷凝过程中的热传递。在气相中形成了临时密度和温度梯度。通过逐步改变亚稳态蒸汽的初始饱和度，研究了亚稳态蒸汽从接近双结点的吸附行为到非均相成核的逐渐转变。通过沿等温线增加过饱和度，观察到从逐层生长到逐层岛状生长的连续转变。将所得结果与非均相二维和三维生长模型的经典成核理论进行了比较。我们发现，对于这个体系，经典的非均相成核理论的二维版本最适合描述原子核。
Heterogeneous nucleation and growth of supersaturated argon vapor at polyethylene surfaces is investigated using molecular dynamics simulation. The specific system is chosen as model for high wettable systems. The simulations are conducted in a nonequilibrium ensemble which includes heat transfer during the condensation process. Temporary density and temperature gradients are developed in the vapor phase. The gradual transition from nearly adsorption behavior close to the binodal to heterogeneous nucleation of a metastable vapor is investigated by stepwise varying the initial saturation of the vapor. By increasing the supersaturation along an isotherm a continuous transition from the layer-by-layer growth to the islands-on-layers one is observed. The results are compared to classical nucleation theory for the heterogeneous two- and three-dimensional growth models. We find for this system that a two-dimensional version of the classical heterogeneous nucleation theory is most suitable to describe the nuclea...