Modelling a polyelectrolyte system in water to estimate the ion-conductivity

Atomistic molecular modelling has been utilized to construct a proton-condu cting polymer electrolyte system consisting of poly(ethylene oxide) sulfoni c acid anion (PEO sulfonic acid anion), water, hydronium ion and proton in an amorphous cell. The forcefield was parametrized to simulate proton trans port as accurately as possible in an atomistic model. The coordination stud y was made and found to be mainly in accordance with experimental data. The diffusion coefficients for the PEO sulfonic acid anion, water, the proton and for the hydronium ion were determined. The ion conductivities of the wh ole system and of the ions were estimated and found to be in accordance wit h experimental values. The good correlation between the experimental and si mulated results shows that the used model may provide guidance for evaluati ng new materials by experimentalists. (C) 1999 Elsevier Science Ltd. All ri ghts reserved.