✦ LIBER ✦

Influence of the cation distribution in zeolites on the isotropic 29Si NMR chemical shift

✍ Scribed by P.J. Grobet; W.J. Mortier; K. Van Genechten

Publisher: Elsevier Science
Year: 1985
Tongue: English
Weight: 223 KB
Volume: 119
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(85)80433-4

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✦ Synopsis

The "!%I MAS NMR spxu-um or dehydrawd CaY zeobm IS comphcared wilh re_~pec~ LO the h>drakd SKILS .md show_+ ~1 leasr IWO extra hncs. The spectrum can be ralionahzed by assuming each 01 the lour Si( JIAI) Imes LO be sp11~ IIIICI 1-o Iins nith a chemical shah difrerence of 8 8 ppm and XI inlensiIy ratio or 0.7. This model. descrlbmg the influence or the Cd ion distribution on the '%i NMR speculum. is supporled by the crystal structure. recorded under siml1.w condr[mns. and Ao hy Ihe S/AI ra110 derived rrom the mwnsiks or these doublels

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