Brillouin and Raman spectroscopies were used to investigate the structure of xAl203.(72.08-x) Si02.14.81Na20.11.85Mg0.1.26Eu203 (x=O, 2.96, 5.92, 8.88, 14.81 mol%) and yNa20. (83.93-y) SiO2.2.96Al203.11.85MgO.1.26Eu2O3 (y=9.86, 14.81, 19.73, 24.67 mol%) glasses. The depolymerisation of the Eu3+ doped soda magnesia aluminosilicate (EDSMAS) glass is mainly characterised by the presence of nonbridging (bridging) oxygens and three (four) member silicate and aluminosilicate rings. The aluminium formers entering the glass recover Si-O-Si bridges by attracting charge balancing modifiers from depolymerized SiO4 network. In this way the (Si,Al)4 rather than (SiAl)3 membered rings are formed, i.e. the overall structure becomes more polymerised rather than fragmented. This is supported by the glass elastic constants and moduli as measured by Brillouin spectroscopy.
