Dielectric properties of ethylene carbonate and propylene carbonate using molecular dynamics simulations

Ethylene carbonate (EC) and propylene carbonate (PC) are widely used solvents in Li-ion batteries and supercapacitors. Ion dissolution and diffusion in those media are correlated with solvent dielectric responses. Here, we use all-atom molecular dynamics simulations of the pure solvents to calculate dielectric constants and relaxation times. The dielectric constant measures polarization of a material by a static applied field while the relaxation assesses the lag of the polarization in responding to a changing applied field. Predicted values are compared with the available experimental results to validate the force field parameters (OPLS-AA) for these solvents. Results for dielectric constants and relaxation times agree with experiment for both EC and PC.