Effective Potential Theory for Diffusion in Binary Ionic Mixtures

TL;DR

This paper evaluates the effectiveness of the Effective Potential Theory in predicting diffusion coefficients in binary ionic mixtures, showing good agreement with molecular dynamics simulations across various coupling regimes.

Contribution

It demonstrates that EPT accurately predicts diffusion in binary ionic mixtures from weak to strong coupling, extending its validated range.

Findings

EPT agrees with molecular dynamics within 20-40% error

EPT is effective across weak to strong coupling regimes

Darken model's approximation is also examined

Abstract

Self-diffusion and interdiffusion coefficients of binary ionic mixtures are evaluated using the Effective Potential Theory (EPT), and the predictions are compared with the results of molecular dynamics simulations. We find that EPT agrees with molecular dynamics from weak coupling well into the strong coupling regime, which is a similar range of coupling strengths as previously observed in comparisons with the one-component plasma. Within this range, typical relative errors of approximately 20% and worst-case relative errors of approximately 40% are observed. We also examine the Darken model, which approximates the interdiffusion coefficients based on the self-diffusion coefficients.