Raman study of beta-irradiated glasses

The ageing processes of nuclear glasses under irradiation have been simulat ed on three simple glass compositions (4-, 5- and 6-oxide glasses) by exter nal beta-irradiation. The structure of these glasses has been studied by Ra man spectroscopy, and all three exhibit similar evolution under irradiation . The main findings are: (i) an increase of the network polymerization rela tive to the non-irradiated samples, (ii) an increase in concentration of mo lecular O-2 and (iii) a decrease of the average Si-O-Si bond angle. These d ata confirm the structural effects of the migration of sodium ions under ex ternal irradiation. (C) 1999 Elsevier Science B.V. All rights reserved.