2001, Peuker, Christel, Brzezinka, Klaus-Werner, Gaber, Martin, Kohl, Anka, Geißler, Heinz

IR spectra of a deuterated glass of the composition (in mol%) 16 Na2O · 10 CaO · 74 SiO2 complete earlier spectroscopic studies on water-poor soda-lime-silica glasses. The approved IR spectroscopic method of the deuterium exchange allows a reliable assignment of the hydroxyl bands also in the case of glasses. By spectra comparison the assignment of the IR bands at 3500 and 2800 cm-1 to hydroxyl groups with different hydrogen bonding is verified. The IR band at about 4500 cm-1 is interpreted as both a combination of the stretching vibrations vO-H and vSi-OH and a combination of the stretching vibration vO-H and the deformation vibration δSiOH. The bands at 1763 and 1602 cm-1 are attributed to combination vibrations of the glass network.

2002, Peuker, Christel, Bessau, Waltraud, Brzezinka, Klaus-Werner, Kohl, Anka, Reinholz, Uwe, Geißler, Heinz

Vibrational spectra are measured for calcium aluminosilicate glasses with the composition (in mol%) xCaO ∙ xAI2O3 ∙ (100 - 2x)SiO2. The OH bands show a systematic change with x in both MIR and NIR regions. The strongly asymmetric band at about 3550 cm-1 shifts to lower wave numbers with increasing x. In the same way the OH combination band at about 4500 cm-1 shifts to lower wave numbers. For the 3550 cm-1 band an extinction coefficient of about 60 1 ∙ mol-1 ∙ cm-1 is suggested for all the samples with x from 15 to 32. For the 4500 cm-1 band the extinction coefficient decreases from 1.0 to 0.49 1 ∙ mol-1 ∙ cm-1 with increasing x from 15 to 32. Systematic changes in the Raman and IR reflectance spectra reflect the substitution of Al3+ for Si4+ and a corresponding increase of Ca2+ in the network. Thus, the vibrational spectra can be related to a fully polymerized network without or with a small amount of nonbridging oxygens also for glasses with x ≥ 25.