Tests of the homogeneous nucleation theory with molecular-dynamics simulations. I. Lennard-Jones molecules.
Tests of the homogeneous nucleation theory with molecular-dynamics simulations. I. Lennard-Jones molecules.
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DOI：
10.1063/1.1896345
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发表时间：
2005-05
期刊：
影响因子：
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通讯作者：
Kyoko K. Tanaka;K. Kawamura;Hidekazu Tanaka;K. Nakazawa
中科院分区：
文献类型：
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作者：
Kyoko K. Tanaka;K. Kawamura;Hidekazu Tanaka;K. Nakazawa
目前存在两种均匀形核理论：经典形核理论和半唯象模型。为了测试它们，我们用5000- 20，000个Lennard-Jones型分子进行了从蒸汽到液体的成核的分子动力学（MD）模拟。模拟进行了各种值的过饱和比（从2到10）和温度（从80到120 K）。我们比较了分子动力学模拟中团簇的尺寸分布与理论模型中的尺寸分布，因为临界团簇的数量密度决定了成核速率。我们发现，semiphenomenological模型取得了很好的协议与我们所做的所有MD模拟团簇的大小分布。经典理论在80-100 K温度范围内低估了团簇的数密度，而在100-120 K温度范围内高估了团簇的数密度。在分子动力学模拟中，半唯象模型也能很好地预测成核速率，而经典成核理论不能。我们的结果证实了Lennard-Jones型分子的半唯象模型的有效性。
Two kinds of the homogeneous nucleation theory exist at the present: the classical nucleation theory and the semiphenomenological model. To test them, we performed molecular-dynamics (MD) simulations of nucleation from vapor to liquid with 5000-20,000 Lennard-Jones-type molecules. Simulations were done for various values of supersaturation ratios (from 2 to 10) and temperatures (from 80 to 120 K). We compared the size distribution of clusters in MD simulations with those in the theoretical models because the number density of critical clusters governs the nucleation rate. We found that the semiphenomenological model achieves excellent agreements in size distributions of the clusters with all MD simulations we done. The classical theory underestimates the number density of the clusters in the temperature range of 80-100 K, but overestimates in 100-120 K. The semiphenomenological model also predicts well the nucleation rate in MD simulations, while the classical nucleation theory does not. Our results confirmed the validity of the semiphenomenological model for Lennard-Jones-type molecules.