An electrodiffusion model for Jaccard's theory in ice

Abstract

Jaccards' theory describes the movement of both ionic and Bjerrum defects in ice. Standard descriptions of the theory are based on a chain model describing the movement of these defects along well-oriented chains of water molecules. However, this model contains several fundamental contradictions and does not result in the exact equations. We present an alternative model based on the electrodiffusion of the defects. The polarisation of the ice specimen favours these defects orientations that diffuse opposite to the electric drift of the same defect. This straightforward approach not only results in the correct equations, it also provides a better understanding of the defects' kinetics.