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Octahedral sites in talc revisited: an EPR study

Published online by Cambridge University Press:  09 July 2018

P. M. Schosseler
Affiliation:
Laboratory for Physical Chemistry, Swiss Federal Institute of Technology, ETH, CH-8092 Zurich, Switzerland
P. G. Weidler
Affiliation:
Institute of Terrestrial Ecology, Swiss Federal Institute of Technology, ETH, CH-8952 Schlieren, Switzerland
A. U. Gehring
Affiliation:
Institute of Terrestrial Ecology, Swiss Federal Institute of Technology, ETH, CH-8952 Schlieren, Switzerland

Extract

Talc [ideal formula: Mg3Si4O10(OH)2] is one of the classical 2:1 trioctahedral phyllosilicates that has been analysed intensively with respect to its formation, thermal stability, chemical properties and structure (e.g. Wilkins & Ito, 1967; Rayner &Brown, 1973; Ward, 1975; Martin et al., 1996). Single crystal structure refinement by X-ray diffraction (XRD) showed clearly that talc is triclinic and crystallizes in the space group CI (e.g. Rayner & Brown, 1973; Perdikatsis & Burzlaff, 1981). Based on this structural model, two coordination arrangements of OH groups to Mg in the octahedral sheets can be deduced. Since XRD data give only an insight into the average structure, local information on the ligand field of the cations is limited. Currently, no analytical tool is known to determine directly the ligand field of Mg in the octahedral sites.

Type
Notes
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1998

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