Lu Hao, Xu Quanming, Wu Jianyang, Hong Rongdun, Zhang Zhisen
Department of Physics, Research Institute for Biomimetics and Soft Matter, Fujian Provincial Key Laboratory for Soft Functional Materials Research, Jiujiang Research Institute, Xiamen University, Xiamen, Fujian 361005, People's Republic of China.
J Phys Condens Matter. 2021 Jul 14;33(37). doi: 10.1088/1361-648X/ac0f2c.
In this work, we performed molecular dynamics simulations of ice nucleation on a rigid surface model of cubic zinc blende structure with different surface dipole strength and orientation. Our results show that, although substrates are excellently lattice-matched to cubic ice, ice nucleation merely occurred as the interfacial water molecules (IWs) show identical or similar orientations to that of water molecules in cubic ice. Free energy landscapes revealed that, as substrates have non-suitable dipole strength/orientation, there exist large free energy barriers for rotating dipole IWs to the right orientation to trigger ice formation. This study stresses that, beyond the traditional view of lattice match and the similarity of lattice length between the substrate and new-formed crystal, the similarity between molecular orientations of interfacial component and component in the specific new-formed crystalline face is also critical for promoting ice nucleation.
在这项工作中，我们对具有不同表面偶极强度和取向的立方闪锌矿结构刚性表面模型上的冰核形成进行了分子动力学模拟。我们的结果表明，尽管衬底与立方冰具有出色的晶格匹配，但只有当界面水分子（IW）与立方冰中的水分子呈现相同或相似的取向时，冰核才会形成。自由能景观显示，当衬底具有不合适的偶极强度/取向时，将偶极IW旋转到正确取向以触发冰形成存在很大的自由能垒。这项研究强调，除了传统的晶格匹配观点以及衬底与新形成晶体之间晶格长度的相似性之外，界面成分与特定新形成晶面中成分的分子取向相似性对于促进冰核形成也至关重要。
