A study was made of the dynamics of sodium atoms in amorphous Na2O-4SiO2. It was found that the sodium trajectories formed a well connected network of pockets and pathways that were intimately related to the location of the non-bridging oxygen atoms. Inside these channels the sodium atoms moved by activated jumps. By determining the probability that an atom returned to a given starting site, it was shown that, for the present concentration of sodium at 1600 to 4000K, such events were not important to the dynamics of this system.

Molecular Dynamics Study of the Diffusion of Sodium in Amorphous Silica. Sunyer, E., Jund, P., Kob, W., Jullien, R.: Journal of Non-Crystalline Solids, 2002, 307-310, 939-45