Far-infrared spectra of the ammonia and hydrogen forms of zeolites of types X and Y

Abstract

Far-infrared spectra of the zeolites NH₄NaX, NH₄NaY, HNaX and HNaY at various degrees of exchange and of their dehydroxylated forms have been measured, and the preferred positions of NH⁺₄ within the zeolites have been estimated. The expected bands corresponding to cation motion of H⁺ or vibrations of hydrogen-bridged OH groups were not detected in the spectra of either the HNaX or HNaY zeolites. Conclusions concerning the arrangement of cations in the zeolites are based on the results of our f.i.r. spectra and on the X-ray diffraction results of other authors for alkali-metal-exchanged zeolites.