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29Si NMR chemical shifts in silicates

✍ Scribed by S. Prabakar; K.J. Rao; C.N.R. Rao

Publisher: Elsevier Science
Year: 1991
Tongue: English
Weight: 553 KB
Volume: 183
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(91)80046-z

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✦ Synopsis

29Si chemical shifts in a wide variety of silicates in crystalline, glassy and gel states have been related to a parameter, P, which takes into account the electronegativity and the structural description of the silicate units as well as the ionic potential of the modifier cation. The relation, G(ppm) =28.4 [ 1 -exp( -P)] -110.5, besides having predictive value, satisfactorily accounts for all the available chemical-shift data on silicates and shows the right kind of limiting behaviour, with S approaching the Q. value at large P. * Contribution No. 782.

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