Dynamic Mirror Image Charge Method for First-Principles-Based Modeling of Surface Polarization at the Electrode-Electrolyte Interface.

Understanding the structure of the electrical double layer (EDL) at the electrode-electrolyte interface is crucial for electrocatalytic and charge storage processes. The EDL structure is strongly influenced by electrode polarization, highlighting the need for accurate modeling of polarization effects. This study introduces a novel simulation method known as dynamic mirror image molecular dynamics (DMI-MD) to incorporate electrode polarization within classical molecular dynamics (MD) simulations. DMI-MD employs a dynamically varying mirror plane whose position depends on the locations of the electrolyte charges. Within the image-charge framework, this approach reproduces the ab initio linear-response electrostatic polarization of the slab, thereby providing a simplified yet accurate representation of complex electrode polarization. Comparative analysis demonstrates the superior performance of this approach over other MD polarization methods, effectively capturing the characteristic camel-shaped double-hump behavior of EDL capacitance. DMI-MD is poised to be a valuable tool for computationally efficient modeling of polarization effects at diverse interfaces within classical MD frameworks.