Molecular dynamics simulations were carried out on a silica glass which contained 1mol%Na2O. The Na distribution was not the same as that found in more highly concentrated Na-containing glasses. Long-range diffusive motion appears to be correlated with the absence of a neighboring non-bridging O. Those Na ions remaining localized often show backward–forward hops that were not readily seen in glasses with larger Na content.

Sodium Ion Migration Mechanisms in Silicate Glasses Probed by Molecular Dynamics Simulations. A.N.Cormack, J.Du, T.R.Zeitler: Journal of Non-Crystalline Solids, 2003, 323[1-3], 147-54