Fast ionic conduction in solid Na3PO4 was studied by using molecular dynamics simulations based upon the modified Lu-Hardy approach. Reasonable agreement with experiment was obtained for the structural transition and for the diffusion of Na ions. All of the Na ions were found to contribute comparably to the high ionic conductivity. The simulation results were explained in terms of the relative magnitudes of the 2 proposed transport mechanisms: percolation and paddle-wheel. It appeared that the percolation mechanism dominated Na diffusion.

Superionicity in Na3PO4 - a Molecular Dynamics Simulation. W.G.Yin, J.Liu, C.G.Duan, W.N.Mei, R.W.Smith, J.R.Hardy: Physical Review B, 2004, 70[6], 064302 (6pp)