Reiser S, Deublein S, Vrabec J, Hasse H
Laboratory of Engineering Thermodynamics, University of Kaiserslautern, 67663 Kaiserslautern, Germany.
Thermodynamics and Energy Technology, University of Paderborn, 33098 Paderborn, Germany.
J Chem Phys. 2014 Jan 28;140(4):044504. doi: 10.1063/1.4858392.
Thermodynamic properties of aqueous solutions containing alkali and halide ions are determined by molecular simulation. The following ions are studied: Li(+), Na(+), K(+), Rb(+), Cs(+), F(-), Cl(-), Br(-), and I(-). The employed ion force fields consist of one Lennard-Jones (LJ) site and one concentric point charge with a magnitude of ±1 e. The SPC/E model is used for water. The LJ size parameter of the ion models is taken from Deublein et al. [J. Chem. Phys. 136, 084501 (2012)], while the LJ energy parameter is determined in the present study based on experimental self-diffusion coefficient data of the alkali cations and the halide anions in aqueous solutions as well as the position of the first maximum of the radial distribution function of water around the ions. On the basis of these force field parameters, the electric conductivity, the hydration dynamics of water molecules around the ions, and the enthalpy of hydration is predicted. Considering a wide range of salinity, this study is conducted at temperatures of 293.15 and 298.15 K and a pressure of 1 bar.
通过分子模拟确定含有碱金属离子和卤离子的水溶液的热力学性质。研究了以下离子:Li(+)、Na(+)、K(+)、Rb(+)、Cs(+)、F(-)、Cl(-)、Br(-)和I(-)。所采用的离子力场由一个 Lennard-Jones(LJ)位点和一个大小为±1 e 的同心点电荷组成。水采用 SPC/E 模型。离子模型的 LJ 尺寸参数取自 Deublein 等人[《化学物理杂志》136, 084501 (2012)],而 LJ 能量参数是本研究根据碱金属阳离子和卤离子在水溶液中的实验自扩散系数数据以及离子周围水的径向分布函数第一个最大值的位置确定的。基于这些力场参数,预测了电导率、离子周围水分子的水合动力学以及水合焓。考虑到较宽的盐度范围,本研究在温度为 293.15 和 298.15 K 以及压力为 1 bar 的条件下进行。