Study of the Features of the Formation of Water Films on the Surfaces of Montmorillonite and Kaolinite by Infrared Spectroscopy

Reference samples of kaolinite KGa-1b and montmorillonite STx-1b have been studied by infrared spectroscopy at different humidity. The spectral features reflecting the formation of water layers on the basal surfaces of individual minerals have been studied. The experimental studies have been performed using infrared spectroscopy of disturbed total internal reflection. The composition of wet samples has been analyzed by decomposing the experimental spectra into the spectrum of H2O and used minerals in the air-dry state. The obtained dependences of the coefficients of participation of the basic spectra on humidity have been compared with the results of the measurements in the ultrahigh frequency range and they allow us to study the integral features of the formation of a water layer on mineral particles and to evaluate the plastic characteristics of clays. The anomalous position of the maximum and the half-width of the band of valence vibrations of water at low humidity have been found.