(374m) A Fast Spectral Method for Field-Induced Behavior of Dense Electrolytes in Confined Geometries

We develop a fast, spectral, solver for the problem of electroosmosis in nanochannels. Our numerical algorithm brings together a spectral Stokes solver for fluid flow [Hashemi et al. J. Chem. Phys. 158, 154101 (2023)] and a spectral Poisson solver for electrostatics [Maxian et al. J. Chem. Phys. 154, 204107 (2021)] to compute the dynamics of the ions. The individual ions are modeled as Brownian particles with Gaussian charges, and interact with each other and the walls of the channel electrostatically, hydrodynamically, and via a steric Lennard-Jones like potential. We rigorously test our solver, which is implemented in graphical processing units, against various theories and established solvers. Our solver allows accurate simulation of field-driven flows in confined geometries under realistic conditions (e.g., high ionic strengths and surface charges), and hence, provides opportunities for an in-depth analysis of such systems.