Structural Investigations of Natural and Synthetic Chlorite Minerals by X-ray Diffraction, Mössbauer Spectroscopy and Solid-State Nuclear Magnetic Resonance

Content Provider	Semantic Scholar
Author	Zazzi, Åsa Hirsch, Tomas K. Leonova, Ekaterina Kaikkonen, Andrei Grins, Jekabs Annersten, Hans Edén, Mattias
Copyright Year	2006
Abstract	The structures of one synthetic and two natural chlorites of the chlinochlore type were explored using X-ray diffraction, magic-angle spinning nuclear magnetic resonance (NMR) and Mössbauer spectroscopy. Rietveld refinements indicated that all structures are of the trioctahedral ordered IIb polytype. Mössbauer spectra provided the ratio IIFe/IIIFe but gave no evidence for the presence of IIIFe in the brucite-like sheet. We also report unit-cell parameters, Mössbauer isomeric shifts, Si NMR chemical shifts as well as 27Al isotropic shifts and quadrupolar coupling parameters. Very broad 29Si NMR peaks from the natural samples prevented us from obtaining accurate information on the Si-Al ordering in the tetrahedral sheets; the limitations of 29Si NMR as applied to natural chlorites are discussed. High-resolution 3QMAS NMR resolved the 27Al signal of the M4 octahedral site in the brucite-like sheet from the other three Al signals of crystallographically inequivalent octahedral positions.
Starting Page	252
Ending Page	265
Page Count	14
File Format	PDF HTM / HTML
DOI	10.1346/CCMN.2006.0540210
Volume Number	54
Alternate Webpage(s)	http://www.clays.org/JOURNAL/archive/Volume%2054/54_2_252.pdf
Alternate Webpage(s)	https://doi.org/10.1346/CCMN.2006.0540210
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article