A three-dimensional cellular automation model is applied to study the spatial distribution of water molecules contacting a structureless planar electrode. Water molecules occupying each cell are modeled as electric dipoles comprising separated positive and negative charges. Electrostatic interactions between cells are computed to determine local torques on water dipoles which drive their tendency to rotate. At the same time, the dipole rotational response is modeled as a thermally activated event that occurs probabilistically, mimicking the thermal activation processes so prevalent in nature. Interfacial phenomena, such as the parallel alignment of water molecules to a neutral planar electrode as well as the transition of dipole orientations in response to the magnitude and sign of charges on the electrode, emerge spontaneously from the simulation. When solvated ions are available in the water, attraction and repulsion due to charges resident on the electrode cause a non-uniform distribution of anions and cations. The simulation results presented in this paper, including the computed distribution profiles for anions and cations influenced by the electrode charge density, as well as the resulting electric fields, electric potential distributions, and the variation of the dielectric constant of water, are consistent with theoretical calculations and existing simulations based on molecular dynamics, opening the door to a new way to simulate such phenomena.
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