Polar-solvation classical density-functional theory for electrolyte aqueous solutions near a wall.
Polar-solvation classical density-functional theory for electrolyte aqueous solutions near a wall.
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DOI：
10.1103/physreve.93.042607
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发表时间：
2016-04
期刊：
影响因子：
--
通讯作者：
Marucho M
中科院分区：
文献类型：
--
作者：
Warshavsky V;Marucho M
准确描述液态水的结构和介电性质对于理解电解质溶液中溶质的物理化学性质是至关重要的。在本文中，离子硬球和偶极硬球的混合考虑了均匀带电硬壁附近离子双电层上的水拥挤和极化效应。作为一个独特的特征，中心带有偶极的溶剂硬球被用来在实验已知的浓度、分子大小和偶极矩下模拟水分子。用极化溶剂化经典密度泛函理论(PSCDFT)计算了该电解质水溶液模型的平衡离子密度和偶极密度分布。这些分布被用来计算电荷密度分布、水极化、介电常数函数、平均电势分布以及微分电容、超额吸附和壁液表面张力。将这些结果与纯偶极模型和电解质水溶液的非极性原始溶剂模型进行了比较，以了解水拥挤和极化效应对这些体系的结构和热力学性质的影响。总体而言，PSCDFT的预测与现有的实验数据是一致的。
A precise description of the structural and dielectric properties of liquid water is critical to understanding the physicochemical properties of solutes in electrolyte solutions. In this article, a mixture of ionic and dipolar hard spheres is considered to account for water crowding and polarization effects on ionic electrical double layers near a uniformly charged hard wall. As a unique feature, solvent hard spheres carrying a dipole at their centers were used to model water molecules at experimentally known concentration, molecule size, and dipolar moment. The equilibrium ionic and dipole density profiles of this electrolyte aqueous model were calculated using a polar-solvation classical density-functional theory (PSCDFT). These profiles were used to calculate the charge density distribution, water polarization, dielectric permittivity function, and mean electric potential profiles as well as differential capacitance, excess adsorptions, and wall-fluid surface tension. These results were compared with those corresponding to the pure dipolar model and unpolar primitive solvent model of electrolyte aqueous solutions to understand the role that water crowding and polarization effects play on the structural and thermodynamic properties of these systems. Overall, PSCDFT predictions are in agreement with available experimental data.