Liu Li-Min, Krack Matthias, Michaelides Angelos
Department of Chemistry and London Centre for Nanotechnology, University College London, London WC1E 6BT, United Kingdom.
J Chem Phys. 2009 Jun 21;130(23):234702. doi: 10.1063/1.3152845.
Density functional theory (DFT) molecular dynamics simulations of a thin (approximately 15 A) water film on NaCl(001) have been performed, with the aim of understanding the structural and dynamic properties of this important interfacial water system. The interaction of the water film with the surface orders the water molecules in the immediate vicinity of the interface. This is reflected by oscillations in the planar-averaged water density distribution along the surface normal that extend to about 8 A from the surface. The interaction with the substrate leaves many of the water molecules in the immediate vicinity with broken hydrogen bonds and as a consequence considerably reduced dipole moments. Indeed a clear correlation between the number of hydrogen bonds which a water molecule is involved in and its dipole moment for both water on NaCl and bulk water is observed. How the DFT results obtained here compare to those obtained with various empirical potentials is briefly discussed.
已对NaCl(001)上的薄水膜（约15埃）进行了密度泛函理论(DFT)分子动力学模拟，目的是了解这个重要的界面水系统的结构和动力学性质。水膜与表面的相互作用使界面附近的水分子有序排列。这表现为沿表面法线方向的平面平均水密度分布的振荡，该振荡从表面延伸至约8埃。与基底的相互作用使紧邻基底的许多水分子的氢键断裂，结果偶极矩大幅降低。实际上，对于NaCl上的水和体相水，都观察到了水分子参与的氢键数量与其偶极矩之间的明显相关性。本文简要讨论了此处获得的DFT结果与用各种经验势获得的结果相比情况如何。
