Raman study of b-irradiated glasses

The ageing processes of nuclear glasses under irradiation have been simulated on three simple glass compositions (4-, 5- and 6-oxide glasses) by external b-irradiation. The structure of these glasses has been studied by Raman spectroscopy, and all three exhibit similar evolution under irradiation. The main findings are: (i) an increase of the network polymerization relative to the non-irradiated samples, (ii) an increase in concentration of molecular O2 and (iii) a decrease of the average Si‐O‐Si bond angle. These data confirm the structural eAects of the migration of sodium ions under external irradiation. ” 1999 Elsevier Science B.V. All rights reserved.