摘要翻译:
用伞状取样法研究了Lennard-Jones液体的均相和非均相成核。确定了形成形核液滴的自由能代价与淬火深度的函数关系,并用干涉技术验证了液滴的鞍点性质。在一定温度范围内发现了成核液滴的结构和对称性。我们发现深淬时,形核液滴变得更加各向异性和弥散,没有明确的核心或表面。成核液滴的环境形成随机堆积的六角形平面。这种行为与调幅形核的解释是一致的。当杂质的晶格间距等于平衡晶相的晶格间距时,异质形核的自由能垒最小。如果杂质的晶格间距不同,晶体生长到块体中而不是润湿杂质。
---
英文标题:
《Homogeneous and heterogeneous nucleation of Lennard-Jones liquids》
---
作者:
Hui Wang, Harvey Gould, and W. Klein
---
最新提交年份:
2007
---
分类信息:
一级分类:Physics 物理学
二级分类:Statistical Mechanics 统计力学
分类描述:Phase transitions, thermodynamics, field theory, non-equilibrium phenomena, renormalization group and scaling, integrable models, turbulence
相变,热力学,场论,非平衡现象,重整化群和标度,可积模型,湍流
--
---
英文摘要:
The homogeneous and heterogeneous nucleation of a Lennard-Jones liquid is investigated using the umbrella sampling method. The free energy cost of forming a nucleating droplet is determined as a function of the quench depth, and the saddle point nature of the droplets is verified using an intervention technique. The structure and symmetry of the nucleating droplets is found for a range of temperatures. We find that for deep quenches the nucleating droplets become more anisotropic and diffuse with no well defined core or surface. The environment of the nucleating droplets form randomly stacked hexagonal planes. This behavior is consistent with a spinodal nucleation interpretation. We also find that the free energy barrier for heterogeneous nucleation is a minimum when the lattice spacing of the impurity equals the lattice spacing of the equilibrium crystalline phase. If the lattice spacing of the impurity is different, the crystal grows into the bulk instead of wetting the impurity.
---
PDF链接:
https://arxiv.org/pdf/706.0328