Surface energy and surface proton order of the ice Ih basal and prism surfaces
Surface energy and surface proton order of the ice Ih basal and prism surfaces
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DOI：
10.1088/0953-8984/22/7/074209
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发表时间：
2010-02
期刊：
影响因子：
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通讯作者：
D. Pan;Li‐Min Liu;G. A. Tribello;B. Slater;A. Michaelides;E. Wang
中科院分区：
文献类型：
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作者：
D. Pan;Li‐Min Liu;G. A. Tribello;B. Slater;A. Michaelides;E. Wang
密度泛函理论（DFT）是用来检查的基础和棱柱表面的冰Ih。获得类似的表面能的两个表面，然而，在每种情况下，表面质子顺序的表面能的强烈依赖性被确定。这种依赖性可以达到绝对表面能的50%，明显大于对质子有序度的体依赖性（<1%），表明冰表面的热力学基态将在高于约72 K的体有序-无序温度时保持质子有序。在基底表面上，这一建议得到了Monte Carlo模拟的支持，该模拟采用了经验势和DFT中最近邻相互作用的二维伊辛模型的解。序参数定义的表面能量的每个表面的悬挂OH键（那些点出的表面到真空）之间的最近邻相互作用的条款已被确定，并进行了讨论。总的来说，这些结果表明，质子有序无序效应对冰表面的稳定性有着深远的影响，并且很可能对冰表面的反应性以及冰晶的生长和形态产生影响。
Density-functional theory (DFT) is used to examine the basal and prism surfaces of ice Ih. Similar surface energies are obtained for the two surfaces; however, in each case a strong dependence of the surface energy on surface proton order is identified. This dependence, which can be as much as 50% of the absolute surface energy, is significantly larger than the bulk dependence (<1%) on proton order, suggesting that the thermodynamic ground state of the ice surface will remain proton ordered well above the bulk order–disorder temperature of about 72 K. On the basal surface this suggestion is supported by Monte Carlo simulations with an empirical potential and solution of a 2D Ising model with nearest neighbor interactions taken from DFT. Order parameters that define the surface energy of each surface in terms of nearest neighbor interactions between dangling OH bonds (those which point out of the surface into vacuum) have been identified and are discussed. Overall, these results suggest that proton order–disorder effects have a profound impact on the stability of ice surfaces and will most likely have an effect on ice surface reactivity as well as ice crystal growth and morphology.