Comparative study of external electric field and potential effects on liquid water ions
Comparative study of external electric field and potential effects on liquid water ions
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DOI：
10.1080/00268976.2021.1998689
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发表时间：
2021-11
影响因子：
1.7
通讯作者：
Satyanarayana Bonakala;M. Hasan
中科院分区：
文献类型：
--
作者：
Satyanarayana Bonakala;M. Hasan
在过去的几十年里，分子动力学模拟被广泛用于研究外电场对水中许多物理过程的影响，包括离子的迁移率、场诱导汽化和电润湿。在大多数这些研究中，电场被作为外力施加到模拟中的所有原子。虽然这种方法是直观和直接的，但它既没有捕捉到水对电场的屏蔽，也没有捕捉到任何界面效应。恒定电极电位法(CPM)允许在系统水平上施加外部电场，类似于实验设置，并考虑了水的屏蔽效应。本文采用CPM方法研究了外加电场对水表面张力的影响，并与传统方法进行了比较，同时计算了Na+和Cl-−离子在汽液界面上的界面迁移率。这两种方法得到的表面张力随电场的变化趋势相似。与传统方法相比，CPM方法预测的表面张力变化较小，最大偏差为表面张力值的36%。图形摘要
Molecular dynamics simulations were used extensively in the last decades to study the influence of an external electric field on many physical processes in water, including mobility of ions, field-induced vaporisation, and electrowetting. In most of these studies, the electric field was applied as an external force to all atoms in the simulation. While such an approach is intuitive and straightforward, it neither captures the shielding of the electric field by water nor any interfacial effect. The Constant Electrode Potential Method (CPM) allows for an external electric field to be applied on a system level, resembling experimental settings and accounting for shielding effects by water. In this work, the CPM method has been implemented to study the influence of an external electric field on the surface tension of water and to compare that to the conventional method, in addition to computing the interfacial mobilities of Na+ and Cl− ions at a liquid–vapor interface. The two approaches yield a similar trend of surface tension variation with the electric field. The CPM method predicts a weaker variation in the surface tension in comparison to that of the conventional method, with the maximum reported difference being 36% of the surface tension value. GRAPHICAL ABSTRACT