Fast ionic conduction via site percolation in AgI-AgPO3glasses

The measured electrical conductivity of ${\left(\mathrm{AgI}\right)}_x{\left(\mathrm{Ag}\mathrm{P}{\mathrm{O}}_3\right)}_{1-x}$ glasses for $0<x<\mathrm{}0.6\mathrm{}$ follows a power-law characteristic of site percolation. The percolation threshold is 0.3, the critical exponent 3.3, the vulnerability 4.8, and the number of contact sites 2.7. In an atomically disordered solid, the conductivity of the insulating matrix itself increases as the clusters grow in size, but this has little effect on the percolation threshold.