Nuclear magnetic resonance studies of xenon clusters in zeolite NaA
We have observed the equilibrium distribution of Xe atoms trapped in the alpha cages of zeolite NaA at 300 and at 360 K for low to high xenon loadings. The experimental distributions obtained by nuclear magnetic resonance (NMR) spectroscopy differ from two previously proposed statistical distributions. The experimental deviations from these statistical models can be explained by the attractive Xe-Xe interactions which favor clustering at low to medium loading, and the higher energies associated with the overcrowded cage disfavoring clusters of eight Xe atoms at high loadings. The temperature dependence of the {sup 129}Xe NMR chemical shift of each cluster has been measured in the range 188-421 K, except that for Xe{sub 8}, which was determined only up to 300 K. The observed shifts and their temperature dependence are interpreted by using the results of ab initio calculations of the intermolecular shielding function in the {sup 39}Ar system as a model for the {sup 129}Xe system.
- Research Organization:
- Argonne National Laboratory (ANL)
- Sponsoring Organization:
- NSF
- DOE Contract Number:
- AC02-06CH11357
- OSTI ID:
- 943250
- Report Number(s):
- ANL/CMT/JA-38614
- Journal Information:
- J. Chem. Phys., Journal Name: J. Chem. Phys. Journal Issue: 3 ; Feb. 1, 1992 Vol. 96; ISSN JCPSA6; ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- ENGLISH
Similar Records
Measurement of xenon distribution statistics in Na-A zeolite cavities
Xe{sub n} clusters in the alpha cages of zeolite KA.