skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Study by solid-state NMR of /sup 133/Cs and /sup 1/H of a hydrated and dehydrated cesium mordenite

Journal Article · · J. Phys. Chem.; (United States)
DOI:https://doi.org/10.1021/j100297a025· OSTI ID:6389042

The solid-state NMR of /sup 133/Cs and /sup 1/H in Cs-exchanged mordenite has been monitored as a function of dehydration of the zeolite. In the fully hydrated mordenite, /sup 133/Cs(I=7/2) exhibits a single line 64 ppm upfield of aqueous saturated CsCl. The anhydrous sample exhibits two major lines of intensities 3:1 with center of mass at -57 and -190 ppm, respectively, for Cs under magic-angle spinning. The major intensity is upfield of the line observed in the hydrated sample. The electric field gradient parameters for Cs of the anhydrous sample are e/sup 2/qQ = 3.1 MHz and eta = 0.65, which reduced to e/sup 2/qQ = 210 kHz and eta = 0 for the hydrated sample. Assignment for the three sites occupied by Cs in the anhydrous sample and the corresponding chemical shifts are site II, -157 ppm; site IV, -186 ppm; and site VI, -24 ppm after correction for the second-order quadrupolar shift. The static proton spectra decrease in intensity by a factor of 35 between the fully hydrated and anhydrous sample. While maintaining a roughly constant width of 6.6 kHz, the shape of the proton line changes with dehydration and exhibits an anisotropy in the anhydrous sample.

Research Organization:
Iowa State Univ., Ames
DOE Contract Number:
W-7405-ENG-82
OSTI ID:
6389042
Journal Information:
J. Phys. Chem.; (United States), Vol. 91:13
Country of Publication:
United States
Language:
English