Department of Chemistry, University of North Dakota , Grand Forks, North Dakota 58201, United States.
J Am Chem Soc. 2014 Jun 11;136(23):8145-8. doi: 10.1021/ja500621m. Epub 2014 Feb 28.
Using molecular simulation, we shed light on the coupling between the two nonequilibrium processes of demixing and crystallization in mixtures of fully miscible, size-matched, liquid metals. We show that the competition between these processes has a strong impact on the crystallization pathway, leading to the formation of crystal nuclei with large excesses (up to 95%) in the component of higher cohesive energy, and resulting in increases of more than 30% in the free energy barrier of nucleation. The competition between demixing and crystallization goes on to impact the growth process, as shown by the large variations in composition observed at the surface and inside the growing crystallite.
我们使用分子模拟的方法，研究了完全互溶、尺寸匹配的液态金属混合物中两种非平衡过程——分相和结晶之间的耦合关系。结果表明，这两种过程之间的竞争对结晶途径有很大的影响，导致形成高内聚能成分的晶核过剩（高达 95%），并使形核的自由能垒增加超过 30%。分相和结晶之间的竞争还会影响生长过程，从生长晶体的表面和内部观察到的大的组成变化就可以看出这一点。
