Isomorphous substitution and infra-red spectra of the layer lattice silicates

Abstract

Infrared spectra of series of dioctahedral and trioctahedral synthetic clays in the region 400-5000 cm -1 have been obtained. Characteristic changes in the IR spectra with ionic substitution have been observed with both types. From these results some general conclusions concerning the variations of IR spectra with ionic substitution in both groups of clay minerals can be drawn. In many cases quantitative relationships between frequencies or intensities of the characteristic absorption bands and the extent of ionic substitutions could be established. The same parameters can also be used for the location of substituent ions.