The specific features of the dynamics of structure-forming ions in the melt were studied using molecular dynamics and the ion approximation to the interparticle interaction potential. It was shown that the oxygen diffusion mechanism in the pyrophosphate system was generally similar to that for silicate systems. The main difference of the former mechanism was the absence of over-coordinated defect phosphorus-oxygen complexes. Due to the use of long phase trajectories, oxygen diffusion scenarios involving four tetrahedra were detected for the first time. It was demonstrated that the predominant movements of the zinc ion were long (no shorter than 0.25nm) jumps which made it possible to retain a strong correlation of the relative positions of these ions over long (about 0.6nm) distances.

Molecular Dynamics Study of the Mechanism of Ion Diffusion in an Na2O-ZnO-P2O5 Melt. Boiko, G.G., Parkachev, A.V.: Glass Physics and Chemistry, 2003, 29[1], 35-41