论文标题
迈向雪晶体生长的综合模型：10。关于结构依赖性附着动力学的分子动力学
Toward a Comprehensive Model of Snow Crystal Growth: 10. On the Molecular Dynamics of Structure Dependent Attachment Kinetics
论文作者
论文摘要
我研究了水蒸气中冰生长的分子动力学，重点是如何通过依赖边缘的表面扩散来增强附着动力学。尽管在开发该过程的准确物理模型方面存在明显的不确定性，但有可能对表面扩散率和积分密度增强的合理估计，这取决于我们对冰晶生长过程的基本理解。一个定量模型表明，依赖边缘的表面扩散可以大大增强狭窄的刻面表面上的露台成核，尤其是在表面预言开始时。该结果支持我们假设的结构依赖性附着动力学的机制，该机制很容易解释了雪晶生长形态的变化，其中众所周知的Nakaya图中描述了温度。此处描述的许多模型特征可以使用现有的分子结构和冰表面动力学的计算模型进行进一步的定量研究。
I examine the molecular dynamics of ice growth from water vapor, focusing on how the attachment kinetics can be augmented by edge-dependent surface diffusion. Although there are significant uncertainties in developing an accurate physical model of this process, it is possible to make some reasonable estimates of surface diffusion rates and admolecule density enhancements, derived from our basic understanding of ice-crystal growth processes. A quantitative model suggests that edge-dependent surface diffusion could substantially enhance terrace nucleation on narrow faceted surfaces, especially at the onset of surface premelting. This result supports our hypothesized mechanism for structure-dependent attachment kinetics, which readily explains the changes in snow crystal growth morphology with temperature depicted in the well-known Nakaya diagram. Many of the model features described here may be amenable to further quantitative investigation using existing computational models of the molecular structure and dynamics of the ice surface.
