CO2 Diffusion in Various Carbonated Beverages: A Molecular Dynamics Study

Carbonated beverages are widely enjoyed in spare time, yet there remain many physical and chemical processes clouded at the molecular level. In this report, we employ molecular dynamics simulations to estimate the diffusion coefficients of CO₂ and the molecular origin of its variations in three model systems with characteristic features of champagnes, sugar-based cola drinks, and club sodas. The computed diffusion coefficients of CO₂ are in good agreement with experimental data. Analyses of hydrogen bonding and the solvent's structural and dynamic properties reveal that the change of CO₂ diffusion coefficient is closely associated with the diffusional behavior of the solvent water itself, as a result of changes in the number and strength of hydrogen bonding interactions among the species and solvent.