Dielectric Properties of Ethylene Carbonate and Propylene Carbonate Using Molecular Dynamics Simulations

Wednesday, October 14, 2015: 11:00
101-B (Phoenix Convention Center)
X. You (Tulane University), M. Chaudhari (Sandia National Laboratories), S. Rempe (Sandia National Laboratories), and L. R. Pratt (Tulane University)
Ethylene carbonate (EC) and propylene carbonate (PC) are two widely used solvents in Li-ion batteries and supercapacitors. Ion diffusion in these solvents depends strongly on accurate predictions of solvent dielectric properties. We used all-atom molecular dynamics simulations of these pure solvents to calculate dielectric constants and dielectric relaxation times at various temperatures. The dielectric constant measures polarization of a material whereas dielectric relaxation measures the lag of the polarization in a dielectric medium in responding to a change in an applied field. Predicted values are compared with the available experimental results to validate the force field parameters (OPLS-AA) for these solvents. Current results for dielectric constant and dielectric relaxation time indicate that OPLS-AA force field produces reasonable agreement with experiment for both EC and PC.

Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U. S. Department of Energys National Nuclear Security Administration under contract DE-AC04-94AL85000