CD3CN AS A PROBE OF LEWIS AND BRONSTED ACIDITY OF ZEOLITES

The well-known trio of IR bands (A, B, C) at approximately 2800, appro ximately 2400, and approximately 1700 cm-1, typical for strong H compl exes in vapors, liquids, and solids, is also found in CD3CN adsorption on Bronsted sites of HZSM-5 and HY zeolites. The observed CN frequenc ies in interaction with different Bronsted and Lewis sites of these ze olites are quantitatively reproduced by ab initio 3-21 g calculations combined with the frequency scaling procedure.