Prediction of optical properties of commercial soda–lime-silicate glasses containing iron

We provide a new method to predict the optical absorption of soda–lime-silicate glasses containing low levels (≲1 wt%) of iron. We assumed that octahedral and tetrahedral ferric iron as well as octahedral ferrous iron contribute to the optical absorption of the glasses. The absorption coefficients were determined for the respective colorants, and the total transmission spectra were calculated in the wavelength range from 200 to 2100 nm. It has been shown that the calculated spectra agree well with the experimental ones in the entire range of wavelength. We have further calculated such optical properties as visible light transmittance, total solar energy transmittance, and total solar ultraviolet transmittance. It has been demonstrated that these optical properties are satisfactorily reproduced by the calculations.