Anisotropy in growth kinetics at interfaces between proton-disordered hexagonal ice and water:: A molecular dynamics study using the six-site model of H2O
Anisotropy in growth kinetics at interfaces between proton-disordered hexagonal ice and water:: A molecular dynamics study using the six-site model of H2O
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DOI：
10.1016/j.jcrysgro.2005.05.057
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发表时间：
2005-09-15
影响因子：
1.8
通讯作者：
Furukawa, Y
中科院分区：
文献类型：
--
作者：
Nada, H;Furukawa, Y
分子动力学模拟质子无序六角形冰和水之间的界面进行在熔点附近的温度和压力为1个大气压的H2O，这是最近提出的冰和水的熔点附近的模拟研究的六位模型。对冰的基面、棱面和{1 1 2 0}面的界面进行了模拟。冰的生长过程在所有飞机上都能清楚地观察到。观察到，在{1 1 2 0}面上生长期间，{1 1 2 0}面消失，取而代之的是棱柱面。结果表明，在界面处，{1 1 2 0}面的生长速度大于棱柱面的生长速度。在分子尺度上分析了每个界面的结构和每个界面的生长动力学。模拟结果表明，棱柱和{1 1 2 0}平面的界面具有几何粗糙结构，而基面的界面具有分子平坦结构。模拟还表明，在所有平面上，生长发生在界面附近的水的氢键网络的重组。重组在棱镜和{1 1 2 0}平面上以三维方式发生，而在基底平面上以二维方式发生。生长速度的各向异性，这是在本研究中得到的，是定性与以前的实验一致。它表明，目前的结果在界面结构和生长动力学的各向异性定性地解释了宏观形状的冰生长从水在一个真实的系统。(c)2005 Elsevier B. V.保留所有权利。
Molecular dynamics simulations of interfaces between proton-disordered hexagonal ice and water are carried out at a temperature near the melting point and a pressure of 1 atm using the six-site model of H2O, which was recently proposed for simulation studies of ice and water near the melting point. The simulations are performed for the interfaces of basal, prismatic and {1 1 2 0} planes of ice. The growth process of ice is clearly observed on all planes. It is observed, during growth on the {1 1 2 0} plane, the {1 1 2 0} plane disappears and prismatic planes appear instead. The result suggests that the growth velocity at the interface is larger for the {1 1 2 0} plane than for the prismatic plane. The structure of each interface and growth kinetics at each interface are analyzed on a molecular scale. Simulations show the interfaces of the prismatic and the {1 1 2 0} planes have a geometrically rough structure, whereas the interface of the basal plane has a molecularly flat structure. The simulations also show, that on all planes, growth occurs by reorganization of the hydrogen-bonded network in water near the interface. The reorganization occurs three-dimensionally on the prismatic and the {1 1 2 0} planes, whereas two-dimensionally on the basal plane. The anisotropy in the growth velocity, which is obtained in the present study, is qualitatively consistent with previous experiments. It is shown that the present results on the anisotropy in the interface structure and growth kinetics qualitatively explain the macroscopic shape of ice growing from water in a real system. (c) 2005 Elsevier B.V. All rights reserved.