A number of observations related to interfacial electrostatics of polar liquids question the traditional assumption of dielectric theories that bulk dielectric properties can be continuously extended to the dividing surface separating the solute from the solvent. The deficiency of this approximation can be remedied by introducing local interface susceptibilities and the interface dielectric constant. Asymmetries of ionic hydration thermodynamics and of the mobility between cations and anions can be related to different propensities of the water molecules to orient their dipole toward and outward from solutes of opposite charges. This electrostatic asymmetry is reflected in different interface dielectric constants for cations and anions. The interface of water with neutral solutes is spontaneously polarized due to preferential water orientations in the interface. This phenomenon is responsible for a nonzero cavity potential directly related to a nonzero surface charge. This connection predicts that particles allowing a nonzero cavity potential must show mobility in an external electric field even if the net charge of the particle is zero. The theory predicts that a positive cavity potential and a positive surface charge translate to an effectively negative solute charge reported by mobility measurements. Passing of the cavity potential through a minimum found in simulations might be the origin of the maximum of mobility vs the ionic size observed experimentally. Finally, mobility of proteins in the field gradient (dielectrophoresis) is many orders of magnitude greater than predicted by the traditionally used Clausius-Mossotti equation. Two reasons contribute to this disagreement: (i) a failure of Maxwell's electrostatics to describe the cavity-field susceptibility and (ii) the neglect of the protein permanent dipole by the Clausius-Mossotti equation. An analytical relation between the dielectrophoretic susceptibility and dielectric spectroscopy of solutions provides direct access to this parameter, confirming the failure of the Clausius-Mossotti equation in application to protein dielectrophresis.

中文翻译：

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在均匀和非均匀电场中的静电溶剂化和迁移性：从简单离子到蛋白质。

与极性液体的界面静电有关的许多观察结果对介电理论的传统假设提出质疑，即介电理论可以连续扩展到将溶质与溶剂分开的分隔表面。可以通过引入局部界面磁化率和界面介电常数来弥补这种近似的不足。离子水化热力学的不对称性以及阳离子和阴离子之间的迁移率的不对称性可能与水分子将其偶极子朝向相反电荷的溶质定向和向外定向的不同倾向有关。这种静电不对称性反映在阳离子和阴离子的不同界面介电常数上。水与中性溶质的界面由于界面中优先的水取向而自发极化。这种现象导致与非零表面电荷直接相关的非零腔电位。这种联系预测，即使粒子的净电荷为零，允许非零腔势的粒子也必须在外部电场中显示迁移率。该理论预测，通过迁移率测量报告，正腔电位和正表面电荷转化为有效的负溶质电荷。通过模拟中发现的最小值传递腔电势可能是实验中观察到的最大迁移率与离子尺寸的关系。最后，蛋白质在电场梯度（介电泳）中的迁移率比传统使用的Clausius-Mossotti方程所预测的要大许多数量级。造成这种分歧的原因有两个：（i）麦克斯韦静电学未能描述腔场磁化率；（ii）克劳修斯-莫索蒂方程忽略了蛋白质永久偶极子。介电敏感性和溶液的介电谱之间的分析关系提供了直接访问此参数的方法，从而证实了Clausius-Mossotti方程在蛋白质介电泳中的失败。用静电来描述腔场磁化率，以及（ii）通过Clausius-Mossotti方程忽略蛋白质永久偶极子。介电敏感性和溶液的介电谱之间的分析关系提供了直接访问此参数的方法，从而证实了Clausius-Mossotti方程在蛋白质介电泳中的失败。用静电来描述腔场磁化率，以及（ii）通过Clausius-Mossotti方程忽略蛋白质永久偶极子。介电敏感性和溶液的介电谱之间的分析关系提供了直接访问此参数的方法，从而证实了Clausius-Mossotti方程在蛋白质介电泳中的失败。