Correlation between Floppy to Rigid Transitions and Non-Arrhenius Conductivity in Glasses

Non-Arrhenius behavior is observed for a number of virgin potassium silicate glasses (1-x)SiO2-xK2O with a potassium oxide concentration larger than a certain value x = x(c). Recovering of Arrhenius behavior is provided by the annealing that enhances densification. These various results are the manifestation of the floppy or rigid nature of the network. Compositional effects and saturation with temperature can be analyzed with a combination of constraint theory and a point defect model. They underscore the key role played by network rigidity for the understanding of conduction and saturation effects in glassy electrolytes.