Comparison between the classical theory predictions and molecular simulation results for heterogeneous nucleation of argon.
Comparison between the classical theory predictions and molecular simulation results for heterogeneous nucleation of argon.
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DOI：
10.1063/1.2358343
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发表时间：
2006-10
期刊：
影响因子：
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通讯作者：
A. Lauri;E. Zapadinsky;H. Vehkamäki;M. Kulmala
中科院分区：
文献类型：
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作者：
A. Lauri;E. Zapadinsky;H. Vehkamäki;M. Kulmala
我们对Lennard-Jones氩团簇的均匀成核和非均匀成核进行了Monte Carlo模拟。用区别均质和非均质经典成核理论的主要概念--接触参数对模拟结果进行了解释。我们的研究结果表明，乘法概念的经典异质成核理论描述的集群基板相互作用令人惊讶的是，即使是小分子团簇。然而，在氩成核的刚性单层fcc（111）衬底在T=60 K的情况下，氩-衬底原子的相互作用是大约三分之一强的氩-氩相互作用，使用的经典理论的概念的结果在低估的异质成核率由两到三个数量级，即使是大的集群。这种差异的主要贡献是由均匀成核的经典理论的失败，以预测所涉及的能量，使一个分子从蒸汽中的集群包含少于约15个分子的集群。
We have performed Monte Carlo simulations of homogeneous and heterogeneous nucleations of Lennard-Jones argon clusters. The simulation results were interpreted using the major concept posing a difference between the homogeneous and heterogeneous classical nucleation theories-the contact parameter. Our results show that the multiplication concept of the classical heterogeneous nucleation theory describes the cluster-substrate interaction surprisingly well even for small molecular clusters. However, in the case of argon nucleating on a rigid monolayer of fcc(111) substrate at T=60 K, the argon-substrate atom interaction being approximately one-third as strong as the argon-argon interaction, the use of the classical theory concept results in an underestimation of the heterogeneous nucleation rate by two to three orders of magnitude even for large clusters. The main contribution to this discrepancy is induced by the failure of the classical theory of homogeneous nucleation to predict the energy involved in bringing one molecule from the vapor to the cluster for clusters containing less than approximately 15 molecules.