where d is the thickness of the sample, Io and It are the incident and transmitted photon intensities, respectively. The optical band gap energy, Eg was calculated by the interpolation of the linear region to meet ℏω axis at (αℏω)=0. The infrared spectra of the glasses were investigated between 400 and 4000 cm−1 by the KBr technique using a Shimadzu FTIR – 8700 spectrometer.
All the samples were irradiated using a 60Co radioisotope. The dose rate was 1.77 Gy/min. The glass samples were irradiated for the necessary time interval to achieve the desired overall total dose of 2.5 kGy.