To investigate the structural changes during glass formation after hydration, Fourier transform infrared (FT-IR) spectroscopy measurements were performed on pristine glass and hydrated glass samples. FT-IR spectra were acquired using an attenuated total reflection setup (incorporating crystalline ZnSe as the ATR crystal) under ambient conditions using a Spectrum One spectrometer (PerkinElmer) followed by background subtraction. Absorption spectra were collected in the wavenumber region from 500 to 4000 cm -1 . Glass samples were prepared in advance in a closed crucible before testing at ambient temperature.