DYNAMICS IN SUPERIONIC LITHIUM-SULFATE LATTICE - PADDLE WHEEL VERSUS PERCOLATION MECHANISM

Abstract

We present structural and dynamical results for a model of the lithium sulphate lattice in the superionic phase in which the sulphate-sulphate interaction potential is orientationally averaged. The calculated mobility of the cations and also the structure of the lattice agree quite well with the experimental data. This indicates that the paddling effect of the sulphate tetrahedra on the lithium ion mobility (paddle-wheel mechanism) is of minor importance and that the ion transport process is mainly through the percolation mechanism.