[论文解读] Effect of substrate mismatch, orientation, and flexibility on heterogeneous ice nucleation

Miguel Camarillo, J. Oller-Iscar+3 more|arXiv (Cornell University)|Jan 10, 2026

nanoparticles nucleation surface interactions被引用 0

一句话总结

该研究量化晶格失配、基底取向和晶格柔性对使用水基基底和 mW 模型的异质冰核化的影响。结果显示每增加约1%的失配，核化温度约降低4 K；各冰取向的核化能力相近；柔性基底的核化效率更高。

ABSTRACT

Heterogeneous nucleation is the main path to ice formation on Earth. The ice nucleating ability of a certain substrate is mainly determined by both molecular interactions and the structural mismatch between the ice and the substrate lattices. We focus on the latter factor using molecular simulations of the mW model. Quantifying the effect of structural mismatch alone is challenging due to its coupling with molecular interactions. To disentangle both factors, we use a substrate composed of water molecules in such a way that any variation on the nucleation temperature can be exclusively ascribed to the structural mismatch. We find that a one per cent increase of structural mismatch leads to a decrease of approximately 4 K in the nucleation temperature. We also analyse the effect of the orientation of the substrate with respect to the liquid. The three main ice orientations (basal, primary prism and secondary prism) have a similar ice nucleating ability. We finally asses the effect of lattice flexibility by comparing substrates where molecules are immobile with others where a certain freedom to fluctuate around the lattice positions is allowed. Interestingly, we find that the latter type of substrate is more efficient in nucleating ice because it can adapt its structure to that of ice.

研究动机与目标

• 在不 depend on inter-molecular interactions（此处保持原文） 的前提下，分离并量化晶格失配对冰核化的影响。
• 确定不同冰-基底取向对核化能力的影响。
• 评估基底晶格柔性对核化效率的作用。
• 提供在失配基底上核化时界面结构的机制性见解。

提出的方法

• 在 LAMMPS 的 NVT 系综中使用 mW 水模型对拉伸水-基底进行冰核化模拟。
• 在共存条件下通过拉伸/压缩一个冰晶胞来构建基底；定义结构失配 delta = 100*|f-1|。
• 比较两种基底类型：刚性（不可移动）和井状（原子可在势井内漫游）。
• 通过测量诱导时间并计算 J = 1/(2 A t_ind) 来量化核化，定义在 log(J/(m^2 s)) = 23.6 时的 T_n。
• 通过径向分布函数和跨界面的 q12 局部键序参数分析界面结构在相邻层的变化。
• 考察暴露基底的三种冰取向： basal、primary prism（pI）和 secondary prism（pII）。

Figure 3: (a) Potential energy versus time for a trajectory at 272 K (1 K below the melting temperature) on a wells substrate with $\delta=0$ . (b) Potential energy versus time for nine trajectories of a liquid at 245.0 K on a wells substrate with $\delta=7$ . (c) Time evolution of the potential ene

实验结果

研究问题

• RQ1 在固定面积和观测时间下，冰与基底之间的晶格失配如何影响核化温度？
• RQ2 三种主要冰取向（basal、pI、pII）在拉伸水基底上是否表现出相似的核化能力？
• RQ3 基底晶格柔性对异质冰核化的影响是什么？
• RQ4 基底的等向拉伸与压缩对核化温度和速率有何影响？
• RQ5 在失配基底上核化时，液相层和核在界面附近的结构特征是什么？

主要发现

• 结构失配每增加1%，核化温度大致下降约4 K（对刚性和井状基底均适用）。
• 在不同失配下的核化速率-温度曲线彼此平行，呈现出类似线性的 T_n 与 delta 的关系，可外推至共存点（delta=0）。
• 三种冰取向（basal、pI、pII）表现出非常相似的核化能力，效率上差异很小。
• 柔性（井状）基底比刚性基底在更高的温度下启动冰核化（约高出1–2 K），这是因为基底能够适应冰结构。
• 界面附近的液体结构随着失配减小而更接近冰，存在异质性、斑块状的冰样区域而非均匀润湿层；核显示倾斜的分子柱，表明从基底到体相冰的结构逐步恢复。

Figure 4: (a) Heterogeneous nucleation rate versus temperature for the different mismatches and the different kinds of stretched substrates studied in this work as indicated in the legend. These results correspond to the pII orientation (exposing the yz plane of the stretched and replicated unit cel