On the Electrostatic Interaction of Dielectric Particles in an Electrolyte Solution under the Strong Screening Regime

Abstract

The electrostatic interaction between two identical charged dielectric spherical particles in a symmetric electrolyte solution has been studied on the basis of the Poisson–Boltzmann equation. Particular attention has been focused on the case of high surface potentials of the particles, whose radii are significantly larger than the Debye radius. Using the finite element method, the interaction forces between the particles have been calculated under the conditions of a uniform charge distribution on their surfaces and the absence of an external electric field. It has been shown that allowance for the nonlinearity of the Poisson–Boltzmann equation may be necessary even when the surface potentials of the particles are rather low and the formal application of the linearized Poisson–Boltzmann equation may be employed. The results obtained can be useful for understanding the processes that occur in colloidal systems and analyzing experimental data on the interaction of micron-sized particles in electrolyte solutions.