Clustering of silver atoms in hydrogenated silver-sodium exchanged glasses

The diffusional growth regime of silver clusters in hydrogenated silver–sodium exchanged glasses has been numerically analysed. The diffusion coefficients of the three elements that contribute to silver cluster formation, namely H, Ag+, and Ag0, have been established. The activation energy of the reactant Ag0 diffusion coefficient is consistent in the three analysed different experimental results: Ag loss through evaporation, near-surface Ag accumulation, and optical absorption density. The calculated Ag0 diffusion coefficient accounts for the threshold time necessary to obtain a cluster size to give rise to a detectable absorption.