Department of Physics and Optical Science, University of North Carolina at Charlotte, Charlotte, North Carolina 28223, USA.
J Chem Phys. 2011 Jan 28;134(4):044105. doi: 10.1063/1.3530094.
In a preceding paper [J. Chem. Phys. 131, 154103 (2009)], we introduced a new, hybrid explicit/implicit method to treat electrostatic interactions in computer simulations, and tested its performance for liquid water. In this paper, we report further tests of this method, termed the image-charge solvation model (ICSM), in simulations of ions solvated in water. We find that our model can faithfully reproduce known solvation properties of sodium and chloride ions. The charging free energy of a single sodium ion is in excellent agreement with the estimates by other electrostatics methods, while offering much lower finite-size errors. Similarly, the potentials of mean force computed for Na-Cl, Na-Na, and Cl-Cl pairs closely reproduce those reported previously. Collectively, our results demonstrate the superior accuracy of the proposed ICSM method for simulations of mixed media.
在之前的一篇论文中[J. Chem. Phys. 131, 154103 (2009)]，我们引入了一种新的混合显式/隐式方法来处理计算机模拟中的静电相互作用，并对其在液态水中的性能进行了测试。在本文中，我们报告了这种方法的进一步测试，称为虚电荷溶剂化模型（ICSM），用于模拟水中溶剂化的离子。我们发现，我们的模型可以忠实地再现钠离子和氯离子的已知溶剂化性质。单个钠离子的充电自由能与其他静电方法的估计非常吻合，同时提供了更低的有限尺寸误差。同样，计算得到的 Na-Cl、Na-Na 和 Cl-Cl 对的平均力势也与之前报道的结果非常接近。总的来说，我们的结果表明，所提出的 ICSM 方法在混合介质模拟中具有更高的准确性。
