Optimization of classical nonpolarizable force fields for OH- and H3O+
Optimization of classical nonpolarizable force fields for OH- and H3O+
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DOI：
10.1063/1.4942771
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发表时间：
2016-03-14
影响因子：
4.4
通讯作者：
Netz, Roland R.
中科院分区：
文献类型：
--
作者：
Bonthuis, Douwe Jan;Mamatkulov, Shavkat I.;Netz, Roland R.
我们优化了H3O+和OH-的力场，这些力场再现了实验的溶剂化自由能和H3O+、Cl-和Na+OH-溶液的活度，直到1.5mol/L，并根据氢原子的部分电荷和氧原子的Lennard-Jones参数进行了优化。值得注意的是，优化的H3O+力场的氢原子上的部分电荷为0.8+/-0.1垂直条e垂直条-显著高于非极化水模型和H-3(O)+力场的典型值。相反，氢原子上OH-的最佳部分电荷为零。对于H3O+Cl-溶液可以使用标准的结合规则，而对于Na+OH-溶液，我们需要显著增加阴离子-阳离子的有效Lennard-Jones半径。在强调分子内静电学的重要性的同时，我们的结果表明，在不使用原子极化率的情况下，有可能产生热力学上一致的力场。(C)2016 AIP出版有限责任公司。
We optimize force fields for H3O+ and OH- that reproduce the experimental solvation free energies and the activities of H3O+ Cl- and Na+OH- solutions up to concentrations of 1.5 mol/l. The force fields are optimized with respect to the partial charge on the hydrogen atoms and the Lennard-Jones parameters of the oxygen atoms. Remarkably, the partial charge on the hydrogen atom of the optimized H3O+ force field is 0.8 +/- 0.1 vertical bar e vertical bar-significantly higher than the value typically used for nonpolarizable water models and H-3(O)+ force fields. In contrast, the optimal partial charge on the hydrogen atom of OH- turns out to be zero. Standard combination rules can be used for H3O+Cl- solutions, while for Na+OH- solutions, we need to significantly increase the effective anion-cation Lennard-Jones radius. While highlighting the importance of intramolecular electrostatics, our results show that it is possible to generate thermodynamically consistent force fields without using atomic polarizability. (C) 2016 AIP Publishing LLC.