VandeVondele Joost, Mohamed Fawzi, Krack Matthias, Hutter Jürg, Sprik Michiel, Parrinello Michele
Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
J Chem Phys. 2005 Jan 1;122(1):14515. doi: 10.1063/1.1828433.
The performance of density functional theory methods for the modeling of condensed aqueous systems is hard to predict and validation by ab initio molecular simulation of liquid water is absolutely necessary. In order to assess the reliability of these tests, the effect of temperature on the structure and dynamics of liquid water has been characterized with 16 simulations of 20 ps in the temperature range of 280-380 K. We find a pronounced influence of temperature on the pair correlation functions and on the diffusion constant including nonergodic behavior on the time scale of the simulation in the lower temperature range (which includes ambient temperature). These observations were taken into account in a consistent comparison of a series of density functionals (BLYP, PBE, TPSS, OLYP, HCTH120, HCTH407). All simulations were carried out using an ab initio molecular dynamics approach in which wave functions are represented using Gaussians and the density is expanded in an auxiliary basis of plane waves. Whereas the first three functionals show similar behavior, it is found that the latter three functionals yield more diffusive dynamics and less structure.
密度泛函理论方法用于凝聚态水体系建模的性能难以预测，因此通过对液态水进行从头算分子模拟来验证是绝对必要的。为了评估这些测试的可靠性，我们在280 - 380 K的温度范围内进行了16次每次20 ps的模拟，以表征温度对液态水结构和动力学的影响。我们发现温度对成对相关函数和扩散常数有显著影响，在较低温度范围（包括环境温度）的模拟时间尺度上存在非遍历行为。在对一系列密度泛函（BLYP、PBE、TPSS、OLYP、HCTH120、HCTH407）进行的一致性比较中考虑了这些观察结果。所有模拟均使用从头算分子动力学方法进行，其中波函数用高斯函数表示，密度在平面波的辅助基中展开。前三个泛函表现出相似的行为，而后三个泛函产生的动力学更具扩散性，结构更少。
