Simulating the nucleation of water/ethanol and water/n-nonane mixtures: mutual enhancement and two-pathway mechanism.
Simulating the nucleation of water/ethanol and water/n-nonane mixtures: mutual enhancement and two-pathway mechanism.
复制标题
模拟水/乙醇和水/正壬烷混合物的成核：相互增强和双途径机制。
DOI：
10.1021/ja029006
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发表时间：
2003
影响因子：
15
通讯作者：
Michael L. Klein
中科院分区：
文献类型：
--
作者：
Bin Chen;J. Siepmann;Michael L. Klein
结合聚集-体积-偏置和构型-偏置蒙特卡罗算法和伞形采样技术，研究了两种不同的二元汽液成核体系：水/乙醇和水/正壬烷。模拟能够再现这两种体系在实验中观察到的不同的非理想成核行为，即水/乙醇混合物的成核速率相互增强，水/正壬烷混合物的双途径成核。结构分析为观察到的成核行为提供了微观解释。特别是，模拟显示了水/乙醇液滴中乙醇的大量和尺寸相关的表面富集，这证实了先前对该系统的实验解释。即使在小的水/正壬烷簇中也观察到不混溶性，这导致了双途径成核机制。
A combination of the aggregation-volume-bias and configurational-bias Monte Carlo algorithms and the umbrella sampling technique was applied to investigate two different binary vapor-liquid nucleation systems: water/ethanol and water/n-nonane. The simulations are able to reproduce the different nonideal nucleation behavior observed experimentally for these two systems, i.e., the mutual enhancement of nucleation rates for water/ethanol mixtures and the two-pathway nucleation for water/n-nonane mixtures. Structural analysis provides microscopic explanations for the observed nucleation behavior. In particular, the simulations show a large and size-dependent surface enrichment of ethanol in the water/ethanol droplets, which confirms the previous experimental interpretation for this system. The immiscibility observed even for small water/n-nonane clusters causes the two-pathway nucleation mechanism.