Infrared Absorption Spectra of Sodium Silicate Glasses from 4 to 30μ

The infrared absorption spectra of sodium silicate glasses of molar composition Na 2 O·xSiO 2 (where = 5, 4, 3, and 2) were determined with unpolarized radiation in the 4 to 30μ region. The glass spectra showed a definite similarity to the spectra of α‐quartz, with lattice vibrational bands around 1066,786, and 464 cm −1 . As x decreased, some bands shifted toward lower frequencies indicating a decrease in the force constant. No new frequencies were found in the silicate glasses which did not have counterparts in α‐quartz.