The Influence of Distant Boundaries on the Solvation of Charged Particles
The Influence of Distant Boundaries on the Solvation of Charged Particles
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远边界对带电粒子溶剂化的影响
DOI：
10.1007/s10955-019-02274-8
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发表时间：
2019
影响因子：
1.6
通讯作者：
J. Weeks
中科院分区：
文献类型：
--
作者：
Richard C. Remsing;J. Weeks
库仑势的长程性质要求在确定带电溶质的溶剂化自由能时，适当考虑远距离静电边界的影响。我们引入了对充电溶质时自由能变化的精确重写，明确地将贡献从这些边界分离出来，并量化了不同边界对自由能的影响。我们通过研究几个简单的模型电荷分布，证明了适当地将静电势与真空的静电势相参照的重要性和优势，为此，我们可以从分子系统的计算机模拟中容易地估计的边界中分离出解析贡献。最后，我们强调，当溶剂和溶质的电荷分布在相关构型中不重叠时，体介电相的恒定电势--Bethe势--不能对单一带电溶质的溶剂化热力学做出贡献。但当单个溶质的电荷分布与溶剂分子的分子内电荷分布重叠时，例如电子全息术中的情况，与实验相比，需要Bethe势。我们的工作也可能为传统上在单离子溶剂化自由能的实验测定过程中所做的“额外热力学假设”的有效性提供洞察。
The long-ranged nature of the Coulomb potential requires a proper accounting for the influence of even distant electrostatic boundaries in the determination of the solvation free energy of a charged solute. We introduce an exact rewriting of the free energy change upon charging a solute that explicitly isolates the contribution from these boundaries and quantifies the impact of the different boundaries on the free energy. We demonstrate the importance and advantages of appropriately referencing the electrostatic potential to that of the vacuum through the study of several simple model charge distributions, for which we can isolate an analytic contribution from the boundaries that can be readily evaluated in computer simulations of molecular systems. Finally, we highlight that the constant potential of the bulk dielectric phase—the Bethe potential—cannot contribute to the solvation thermodynamics of a single charged solute when the charge distributions of the solvent and solute do not overlap in relevant configurations. But when the charge distribution of a single solute can overlap with the intramolecular charge distribution of solvent molecules, as is the case in electron holography, for example, the Bethe potential is needed when comparing to experiment. Our work may also provide insight into the validity of “extra thermodynamic assumptions” traditionally made during the experimental determination of single ion solvation free energies.
影响因子：
3.3
作者：
Mukhopadhyay, Abhishek;Fenley, Andrew T.;Tolokh, Igor S.;Onufriev, Alexey V.
通讯作者：
Onufriev, Alexey V.
影响因子：
14.7
作者：
England JL;Haran G
通讯作者：
Haran G
影响因子：
4.4
作者：
Harder, Edward;Roux, Benoit
通讯作者：
Roux, Benoit