论文标题
完全周期性的计算有效恒定恒定电势分子动力学模拟的离子液体超电容器
Fully Periodic, Computationally Efficient Constant Potential Molecular Dynamics Simulations of Ionic Liquid Supercapacitors
论文作者
论文摘要
越来越多的复杂电化学系统（例如离子液体超级电容器）的分子动力学（MD）模拟包括恒定电位方法（CPM），以模拟指定的电位差异导电电极，但CPM的包含在计算上可能是昂贵的。当通常的非周期性平板几何形状被完全周期性的边界条件取代时，我们证明了离子液体超级电容器的CPM MD模拟中可用的计算节省。我们展示了以前在带电界面的非CPM MD模拟中使用的双重细胞方法如何用于启用完全周期性的CPM MD模拟。使用两倍的细胞方法或其他人先前报告的有限场方法，完全周期性的CPM MD模拟与传统的板几何模拟仿真可相当，计算时间几乎加速了两倍。确实，这些节省可以抵消CPM算法的额外成本，从而产生周期性的CPM MD模拟，这些模拟比在此研究的离子液体超级电容器的非周期性，固定荷兰等效模拟更快。
Molecular dynamics (MD) simulations of complex electrochemical systems, such as ionic liquid supercapacitors, are increasingly including the constant potential method (CPM) to model conductive electrodes at specified potential difference, but the inclusion of CPM can be computationally expensive. We demonstrate the computational savings available in CPM MD simulations of ionic liquid supercapacitors when the usual non-periodic slab geometry is replaced with fully periodic boundary conditions. We show how a doubled cell approach, previously used in non-CPM MD simulations of charged interfaces, can be used to enable fully periodic CPM MD simulations. Using either a doubled cell approach, or a finite field approach previously reported by others, fully periodic CPM MD simulations produce comparable results to the traditional slab geometry simulations with a nearly double speed-up in computational time. Indeed, these savings can offset the additional cost of the CPM algorithm, resulting in periodic CPM MD simulations that are faster than the non-periodic, fixed-charge equivalent simulations for the ionic liquid supercapacitors studied here.
