FOURIER-TRANSFORM RAMAN-SPECTROSCOPY OF KAOLINITE

The vibrational modes of clay minerals are uniquely accessible to FT R aman spectroscopy. Raman spectra in the 50-3800 cm(-1) region were obt ained for a suite of kaolinite clay minerals. The kaolinite clay miner als are characterized by intense bands centred at 142.7 cm(-1) with a prominent shoulder at 127 cm(-1) and are attributed to the O-Al-O and O-Si-O symmetric bends. Differences in the lattice modes for the kaoli nite clay minerals in the 200-1200 cm(-1) region were obtained. Five h ydroxyl bands were obtained for kaolinite at 3619, 3650, 3667, 3686, a nd 3695 cm(-1); four OH bands were found for dickites at 3621, 3639, 3 652 and 3703 cm(-1).