Computer simulation study of the structure of LiCl aqueous solutions: test of non-standard mixing rules in the ion interaction.
Computer simulation study of the structure of LiCl aqueous solutions: test of non-standard mixing rules in the ion interaction.
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DOI：
10.1021/jp500937h
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发表时间：
2014-05
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影响因子：
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通讯作者：
J. L. Aragones;M. Rovere;C. Vega;P. Gallo
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文献类型：
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作者：
J. L. Aragones;M. Rovere;C. Vega;P. Gallo
LiCl水溶液的过冷水异常及其多晶性研究近年来受到广泛关注。从计算机模拟的角度来看，需要一个能够再现该溶液结构和动力学特性的力场，更重要的是它也足够简单，可以用于大规模的过冷态模拟。利用Joung和Cheatham （J. Phys.）提出的力场，用分子动力学方法研究了licl -水溶液的结构。化学。[j] .岩石力学与工程学报，2009,22(2):391 - 391。我们发现当使用Lorentz-Berthelot （LB）规则时，该力场不能再现实验离子配对。通过对LB规则的偏差计算离子间的交叉相互作用，可以得到与实验相符的结果。我们研究了当溶液浓度从低浓度（约2%）增加到中浓度（约14%）时，LB规则的修改如何影响溶液的结构和热力学性质。我们还测试了young和Cheatham力场在水TIP4P/2005模型中的可转移性，该模型对过冷水非常有效。
Aqueous solutions of LiCl have recently received much attention in connection with the study of the anomalies of supercooled water and its polyamorphism. From the point of view of computer simulation, there is need for a force field that can reproduce the structural and dynamical properties of this solution, and more importantly it is also simple enough to use in large scale simulations of supercooled states. We study by molecular dynamics the structure of the LiCl-water solutions with the force field proposed by Joung and Cheatham (J. Phys. Chem. B 2008, 112, 9020) appropriate for the water TIP4P-Ew model potential. We found that this force field does not reproduce the experimental ion pairing when the Lorentz-Berthelot (LB) rules are used. By incorporating deviations to the LB rules to obtain the crossed interactions between the ions, it is possible to get agreement with experiment. We have studied how the modification of the LB rule affects the structural and thermodynamic properties of the solution at increasing concentration of the solution from the low (around 2%) to medium (around 14%) concentration regimes. We also tested the transferability of the Joung and Cheatham force field to the water TIP4P/2005 model that works very well for supercooled water.