Temperature dependence of nuclear magnetic resonance chemical shifts of Xe-129 in the alpha-cages of NaY zeolite

Citation
A. Labouriau et al., Temperature dependence of nuclear magnetic resonance chemical shifts of Xe-129 in the alpha-cages of NaY zeolite, J PHYS CH B, 103(21), 1999, pp. 4323-4329
Citations number
48
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
JOURNAL OF PHYSICAL CHEMISTRY B
ISSN journal
15206106 → ACNP
Volume
103
Issue
21
Year of publication
1999
Pages
4323 - 4329
Database
ISI
SICI code
1520-6106(19990527)103:21<4323:TDONMR>2.0.ZU;2-P
Abstract
One- and two-dimensional NMR spectra of Xe-129 sorbed in NaY zeolite at a l oading of approximately 1 Xe atom/4 alpha-cages were obtained as a function of temperature. One-dimensional spectra were measured over the range of 60 -300 K, by far the largest range yet investigated with this method. The dat a were fitted to the simple statistical mechanical cylindrical pore model o f Cheung yielding a van der Waals adsorption energy of 3.3 kJ/mol. 2D-NOESY spectra were obtained at 300 and 355 K. The two-dimensional data show that the intercrystalline diffusion is slow compared to intracrystalline diffus ion. The results indicate that the Xe atoms spend most of their time in the or-cages and at the lower temperatures, near the cage walls.