INFRARED SPECTROSCOPIC INVESTIGATIONS OF ZEOLITES AND ADSORBED MOLECULES. III. SPECTRA OF THE ZEOLITE STRUCTURE.

Part I. J. Phys. Chem. 69, 3463 (1965). Part II. J. Phys. Chem. 70, 1413 (1966).Author Institution: Union Carbide Research InstituteAlthough several papers have been published on the infrared spectra of molecules adsorbed on zeolites, the spectrum of the zeolite structure has not been discussed in detail previously. In the present work the spectra of a number of Linde X- and Y-type zeolites containing uni-and bi-valent cations have been obtained between 2 and 40 microns, and the observed bands have been assigned. Bands appear in the spectrum when the samples are activated in oxygen that are not present in vacuum-activated samples. The behavior of these bands as well as their interpretation will be discussed. Spectral differences between samples containing various cations, between samples in the hydrated and dehydrated forms, and shifts in frequency with silicon-aluminum ration in the X to Y series have also been observed and interpreted. Other portions of this series have appeared previously