ChemInform Abstract: Investigation of the Hydration of Zeolite NaA by Two‐Dimensional 23Na Nutation NMR.

Abstract

010ChemInform Abstract From two-dimensional 23Na spectra of zeolite NaA as a function of water content the following can be concluded: In dry NaA two Na sites can be detected, at the 6-rings and at the 8/4-rings. The first water molecules are absorbed at the 8/4-rings. When the amount of absorbed water is increased in steps, first the quadrupole interaction of Na at the 6-rings decreases; with more absorbed water the quadrupole interaction of the Na ions at the 8-rings becomes small. Relaxation effects in the rotating frame indicate a mobility of Na ions or water molecules. The two-dimensional nutation technique is proved to be very useful for the study of quadrupolar nuclei in zeolites.