Molecular dynamics simulations of lithium metasilicate glass were performed. The motion of Li ions could be divided into slow and fast components. The waiting-time distribution of the jump motion of each component exhibited a power-law behavior, with differing exponents. Slow dynamics were caused by localized jump motions and long waiting times. On the other hand, the fast dynamics of the Li ions could be characterized as being Lévy flights which were caused by cooperative jumps. Short intervals of jump events also occurred in the fast dynamics, in the short term. Both the temporal and spatial terms contributed to the acceleration of the dynamics, and the heterogeneity which was caused by the 2 types of dynamics was illustrated.

Characteristics of Slow and Fast Ion Dynamics in a Lithium Metasilicate Glass. J.Habasaki, Y.Hiwatari: Physical Review E, 1999, 59[6], 6962-6