RAMAN AND INFRARED-SPECTRA OF RARE-EARTH ALUMINOSILICATE GLASSES

Raman and infrared spectra were measured for rare earth aluminosilicat e glasses containing up to 25 mol% of rare earth oxide. Similar spectr a were measured for yttrium alumino/galliosilicate glasses. The result s indicate that the details of the band features of the vibrational sp ectra of these glasses are independent of the specific rare earth ion present. The samarium aluminosilicate system was chosen as a represent ative system for detailed discussion. These glasses contain a broad di stribution of types of nonbridging oxygens, which increase in concentr ation with increasing rare earth oxide concentration. Results of this study agree with structural models proposed on the basis on MAS-NMR an d property studies.