Transport coefficients of the TIP4P-2005 water model.
Transport coefficients of the TIP4P-2005 water model.
复制标题
TIP4P-2005 水模型的输运系数。
DOI：
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复制
发表时间：
2012
影响因子：
4.4
通讯作者：
P. Kusalik
中科院分区：
文献类型：
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作者：
Dmitri A. Rozmanov;P. Kusalik
在分子水平上对液态水动力学的详细了解是至关重要的，并且在许多科学和技术分支中都有应用。本文系统地研究了TIP4P-2005水模型在210-310 K范围内液相中的扩散。研究了平移扩散和旋转扩散，以及它们之间的相关性。本研究还探讨了系统大小和形状的影响。结果表明，分子平移在150-180 K范围内存在动力学阻滞温度，分子旋转在80-130 K范围内存在动力学阻滞温度，这取决于特定的方向。在模型熔化温度略低于（≈15 K）时，观察到相对于分子坐标系的平移和旋转的首选方向发生了实质性变化。结果表明，在液体中扩散所必需的平移和旋转分子运动之间存在相关性。确认并量化了水动力尺寸效应的存在；对液体系统使用非三次模拟盒会导致扩散张量的各向异性分裂。本研究的发现增强了我们对水模型的一般理解，特别是TIP4P-2005模型，并为液态水的热力学与其分子动力学之间的直接联系提供了证据。
A detailed understanding of the dynamics of liquid water at molecular level is of fundamental importance as well as have applications in many branches of science and technology. In this work, the diffusion of the TIP4P-2005 model of water is systematically investigated in liquid phase in the temperature range 210-310 K. The translational and rotational diffusions, as well as correlations between them, are examined. The effects of system size and shape are also probed in this study. The results suggest the presence of a temperature of dynamical arrest of molecular translations in the range of 150-180 K and of molecular rotations in the range of 80-130 K, depending on specific direction. A substantial change in the preferred directions of translations and rotations relative to the molecular coordinate system is observed slightly below (≈15 K) the melting temperature of the model. It is shown that there is a correlation between translational and rotational molecular motions essential for diffusion in the liquid. The presence of hydrodynamic size effects is confirmed and quantified; it is also shown that using a non-cubic simulation box for a liquid system leads to an anisotropic splitting in the diffusion tensor. The findings of this study enhance our general understanding of models of water, specifically the TIP4P-2005 model, as well as provide evidences of the direct connection between thermodynamics of liquid water and dynamics of its molecules.