(304c) Theory of Irreversible Thermodynamics and Non-Equilibrium Statistical Mechanics for Transport Phenomena in Electrolyte Solutions

We develop an irreversible thermodynamics framework for electrolyte transport based on the integration of electromagnetism, continuum mechanics, and classical thermodynamics. Our framework provides balance laws for mass, momentum, energy, and entropy in electrolytes, valid even in non-electroneutral solutions, and captures the coupling of temperature, chemical potential, and electric potential gradients. We utilize this theory to formulate Onsager-type transport equations and a matrix of transport coefficients, which can be combined to obtain experimentally relevant transport quantities such as conductivity and transference number. In contrast to the conventionally-used Stefan-Maxwell coefficients, our transport coefficients can be computed directly from molecular simulations using Green-Kubo relations derived herein, and they have a direct physical interpretation in terms of the correlations between ionic species. We demonstrate the applicability of our theory by computing the transport matrix of LiCl in dimethyl sulfoxide from molecular dynamics, with comparison to experimental measurements. The generalized framework can also be applied to study more complex phenomena such as diffusion in electrolyte solutions with more than two types of ionic species, as well as coupled momentum and charge transport in liquids with dielectric discontinuities.