Vega Carlos, McBride Carl, Sanz Eduardo, Abascal Jose L F
Departamento de Química Fisica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain.
Phys Chem Chem Phys. 2005 Apr 7;7(7):1450-6. doi: 10.1039/b418934e.
Monte Carlo computer simulation studies have been undertaken for virtually all of the ice phases as well as for liquid water for three of the most popular model potentials; namely SPC/E, TIP4P and TIP5P. Densities have been calculated for specific thermodynamic state points and compared to experimental results. The SPC/E and TIP4P models overestimate the solid densities by about 2%. The TIP5P model overestimates the solid densities by about 5-10%. The structural pair correlation functions between oxygen-oxygen, hydrogen-hydrogen and oxygen-hydrogen atoms were also obtained from the simulations. (These are available as ESIt). It has been found that SPC/E and TIP4P structural predictions are rather similar, with the only exception of ice II for which differences are visible between these two models. Predictions from the TIP5P are clearly different from those of the other models, especially for ices Ih and II. For the higher density ices structural differences between the models are rather small. Experimental data would be highly desirable to test the structural predictions of the different models of water. This is especially true for ice II. We have also found that the oxygen-oxygen correlation function of high density amorphous (HDA) water presents the same broad features as those exhibited by ice XII.
针对几乎所有冰相以及液态水,使用三种最流行的模型势开展了蒙特卡罗计算机模拟研究,即SPC/E、TIP4P和TIP5P。计算了特定热力学状态点的密度,并与实验结果进行了比较。SPC/E和TIP4P模型对固体密度的高估约为2%。TIP5P模型对固体密度的高估约为5 - 10%。模拟还得到了氧-氧、氢-氢和氧-氢原子之间的结构对关联函数。(这些可作为ESI获取)。已发现SPC/E和TIP4P的结构预测相当相似,唯一的例外是冰II,这两种模型在冰II上存在明显差异。TIP5P的预测与其他模型明显不同,特别是对于冰Ih和冰II。对于密度更高的冰,模型之间的结构差异相当小。非常需要实验数据来检验不同水模型的结构预测。对于冰II尤其如此。我们还发现,高密度非晶态(HDA)水的氧-氧关联函数呈现出与冰XII相同的宽泛特征。