Mason P E, Brady J W
Department of Food Science, Stocking Hall, Cornell University, Ithaca, New York 14853, USA.
J Phys Chem B. 2007 May 24;111(20):5669-79. doi: 10.1021/jp068581n. Epub 2007 May 1.
Molecular dynamics simulations of pure liquid water under ambient conditions using four common empirical water models have been analyzed to determine how well the oxygen-oxygen radial distribution function, g(OO)(r), used as the sole criterion of congruence with experiment, captures variations in the actual anisotropic collective structuring for these models. The largest systematic deviations from tetrahedrality were found to be due to deformations of the angle between the two closet hydrogen bond donor neighbors, but for intrinsic geometric reasons, these were found to contribute less to g(OO)(r) than deformations of the angles between one hydrogen bond donor neighbor and one hydrogen bond acceptor neighbor. Relying exclusively on a qualitative characterization of the second peak in g(OO)(r) seems to overemphasize the differences between the structuring in some of these models.
利用四种常见的经验水模型对环境条件下纯液态水进行了分子动力学模拟，以确定作为与实验一致性的唯一标准的氧-氧径向分布函数g(OO)(r)能多好地捕捉这些模型中实际各向异性集体结构的变化。发现与四面体结构的最大系统偏差是由于两个最邻近的氢键供体邻居之间的角度变形，但由于内在的几何原因，发现这些偏差对g(OO)(r)的贡献小于一个氢键供体邻居和一个氢键受体邻居之间的角度变形。仅依靠g(OO)(r)中第二个峰的定性特征似乎过分强调了其中一些模型结构之间的差异。
