Quantitative description of self-, Maxwell–Stefan, and Fick diffusion coefficients in sucrose and citric acid solution based on molecular dynamics simulations.

This article focuses on investigating the self-, Maxwell–Stefan (MS), and Fick diffusion coefficients in sucrose (SC)–water and citric acid (CA)–water solutions using molecular dynamics (MD) simulations to better understand diffusion processes relevant to atmospheric aerosol particles. The study finds that diffusion coefficients increase with temperature and decrease with solute mass fraction, with the intensity of these effects varying inversely between temperature and concentration. MD simulation results align well with experimental data, while traditional models such as the McCarty–Mason and Darken equations tend to underpredict diffusion coefficients. Additionally, the authors develop fitting formulas for these diffusion coefficients with high accuracy, underscoring the utility of MD simulations in improving aerosol particle growth models.