Silver as a dopant and as a constituent in As-Ag-Te glasses: Mean atomic volume and T-g

The variations of the mean atomic volume, V, the glass transition temperature, T-g, and the activation energy for glass transition, E(t), with composition have been reported for (As2Te3)(1-x)Ag-x and (As2Te3)-(Ag2Te) glasses; the glasses were prepared by a two-stage melt-quenching method. For the (As2Te3)(1-x)Ag-x glasses, changes in the nature of dependences of V, T-g and E(t) occur at the composition with Ag content of 1 atomic per cent (at.%). Analysis of these results indicates that, for Ag contents less than or equal to 1 at.%, Ag particles are uniformly dispersed in the network of the As,Te, glass, without affecting either the short range or the medium range order of the parent glass. For Ag contents greater than or equal to 3.5 at.%, Ag forms Ag-Te bonds, and the observed variation of the properties can be explained by assuming the resulting three component glasses to be homogeneous mixtures of (As2Te3) and (Ag2Te) units.