| Popis: |
Hydrosodalites and hydroxosodalites were analysed by means of 17 O, 29 Si and 1 H MAS NMR in the fields of 17.6 and 11.7 T. The samples covered a range in Si–O–Al bond angle of about 23. Dependencies between the isotropic 17 O chemical shift dð 17 OÞ and the T–O–T bond angle a for the oxygen sites in sodalites, A and LSX zeolites with Si/Al ¼ 1 were investigated and found to be linear in some special cases. The adsorption of water and/or cation exchange with larger cations increases the 17 O chemical shift. |
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