Quantitative IR spectroscopy: Applications to studying glass structure and properties

A review of data obtainable with various methods of quantitative treatment of the IR spectra of glasses is given. The version of the dispersion analysis method using a specific analytical model for the complex dielectric constant of glasses is shown to be the most appropriate tool for calculating the IR band parameters for glasses. Applications of data on band parameters are illustrated by examples for binary silicate, berate, and germanate glasses. Band parameter versus glass composition plots are discussed and the opportunity to calculate the 'static' dielectric constant corresponding to that characteristic of the ultra high frequency range is shown. The above model uses the convolution of the Lorentzian and Gaussian functions, where the parameters of the Gaussian function characterize the random frequency distributions of the near-zero-wavevector phonon intensities. The idea of such a distribution can be a basis for the semi-empirical calculation of the IR spectra of vitreous solids.