A Coarse-Grained Force Field Parameterized for MgCl2 and CaCl2 Aqueous Solutions
A Coarse-Grained Force Field Parameterized for MgCl2 and CaCl2 Aqueous Solutions
复制标题
MgCl2 和 CaCl2 水溶液的粗粒力场参数化
DOI：
10.1021/acs.jcim.7b00206
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发表时间：
2017-07-01
影响因子：
5.6
通讯作者：
Sun, Huai
中科院分区：
文献类型：
--
作者：
Gong, Zheng;Sun, Huai
钙镁离子在许多物理化学过程中起着重要作用。为了便于调查的现象，这些离子发生在大的长度和时间尺度，一个粗粒力场（CGFF）的MgCl 2和CaCl 2水溶液。离子模型采用具有水化壳层特征的CG珠。为了准确地描述溶液的非理想行为，使用宽浓度范围内的渗透系数作为参数化的指导。渗透系数是由水的化学势增量计算得到的。班尼特接受比（BAR）法。结果CGFF准确地再现了实验的渗透系数，密度，表面张力，氯化钙和氯化镁溶液中的摩尔浓度高达3.0 mol/kg的阳离子-阴离子分离，作为一个初步的应用，力场被施加到模拟十二烷基硫酸钠（SDS）在氯化钙溶液中的聚集，模拟结果与实验观察一致。
Calcium and magnesium ions play important roles in many physicochemical processes. To facilitate the investigation of phenomena related to these ions that occur over large length and time scales, a coarse-grained force field (CGFF) is developed for MgCl2 and CaCl2 aqueous solutions. The ions are modeled by CG beads with characteristics of hydration shells. To accurately describe the nonideal behavior of the solutions, osmotic coefficients in a wide range of concentrations were used as guidance for parametrization. The osmotic coefficients were obtained from the chemical potential increments of water calculated using the. Bennett acceptance ratio (BAR) method. The result CGFF accurately reproduces experimental osmotic coefficients, densities, surface tensions, and cation-anion separations of calcium chloride and magnesium chloride solutions at molalities up to 3.0 mol/kg, As a preliminary application, the force field is applied to simulate aggregations of sodium dodecyl sulfate (SDS) in calcium chloride solution, and the simulation results are consistent with experimental observations.