Orientation-dependent electrostatic interaction between inverse patchy colloids

An inverse patchy colloid (IPC) refers to a particle having patches that are mutually repulsive while the bare particle-patch interactions are attractive. We model a system of charged IPCs with a single patch using Debye-Huckel theory. We derive the full analytical expression for the effective interaction energy for a pair of IPCs as a function of inter-particle separation and particle orientations. The model is applicable for various patch coverage, ionic strengths and dielectric permittivity of the medium. Approximate solutions are derived under high screening limit and the results are compared with the full solution. The model can be used in molecular simulations such as Monte Carlo simulations to accurately describe the interaction between a pair of IPCs for a given experimental conditions.

Automated summary

Inverse patchy colloids (IPC) have unique patch structures with mutual repulsion and attraction. By modeling with Debye-Huckel theory, we derived the effective interaction energy expression for a pair of IPCs, accurately describing particle interactions under various experimental conditions.