NMR-SPECTRA OF MORGANITE AND CHALCEDONY

Citation
H. Graetsch et al., NMR-SPECTRA OF MORGANITE AND CHALCEDONY, European journal of mineralogy, 6(4), 1994, pp. 459-464
Citations number
17
Categorie Soggetti
Mineralogy
ISSN journal
09351221
Volume
6
Issue
4
Year of publication
1994
Pages
459 - 464
Database
ISI
SICI code
0935-1221(1994)6:4<459:NOMAC>2.0.ZU;2-7
Abstract
Si-29 MAS NMR, Si-29 {H-1} CP MAS NMR and H-1 MAS NMR spectra of the w ater-containing micro-crystalline silica varieties chalcedony, moganit e.and three intermediate samples are reported. The Si-29 MAS NMR spect ra give evidence that, unlike quartz, the silicon atoms occupy two sym metrically different sites in moganite. The H-1 MAS NMR spectra show s ignals of molecular water and four different species of silanol groups .