Glass formation and high conductivity in the ternary system AgI+Ag3AsO4+AgPO3: host to glassy AgI?

Wide regions of glass formation have been found in the ternary system xAgI + yAg3AsO4 + (1 - x - y)AgPO3. Glasses containing up to 75 mol % AgI can be formed in sections greater than 2 cm thick without signs of devitrification. Glass transition temperatures as high as 175°C for glasses containing ∼10 mol % AgI fall to ∼45°C at the highest AgI content. An equivalent ratio of AgI:N is defined and it is found that, for all glass-forming compositions, the electrical data as expressed in the Arrhenius form, σ = A exp(-Eact/RT), log (σ/(Ω cm)-1), log (A/(Ω cm)-1), Eact/(kcal mol-1), and additionally Tg/K, can be described as linear functions of N. These data are used to give support to the view of these glasses as being hosts to a "liquidlike" AgI giving rise to the high conductivity they exhibit, as high as 0.0143 (Ω cm)-1 at room temperature for glasses containing the maximum AgI. Finally, from these linear relationships, functions for the mobility μ and number of the mobile Ag+ cations n are developed.