Random distribution of Ge and Si in synthetic talc: an EXAFS and FTIR study
Martin, Francois; Ildefonse, Philippe; Hazemann, Jean-Lοuis; Petit, Sabine; Grauby, Olivier; Decarreau, Alain
European Journal of Mineralogy Volume 8 Number 2 (1996), p. 289 - 300
published: Apr 26, 1996
manuscript accepted: Dec 28, 1995
manuscript received: Mar 23, 1994
ArtNo. ESP147050802004, Price: 29.00 €
Abstract The distribution of Ge and Si atoms within the tetrahedral sheets of the M3(GexSi1-x)4O10(OH)2 talc solid solution (with 0 ≤ x ≤ 1) has been investigated by the Ge K-edge EXAFS and FTIR spectroscopies. Nearest neighbours (Ge, Si) in the tetrahedral sheets appear to be randomly distributed and their average proportion has been determined. Deconvolution of the νM3OH bands in FTIR spectra along the tetrahedral solid solution also indicates non-segregation of Ge and Si atoms within the tetrahedral sheet. The good agreement between these two independent spectroscopic techniques, which are sensitive to the local environment of Ge (short- and medium-range order), demonstrates the reliability of the structural information derived from them.