Determination of the iron oxidation state in Earth materials using XANES pre-edge information

Authors
Petit, PE Farges, F Wilke, M Sole, VA
Citation
Pe. Petit et al., Determination of the iron oxidation state in Earth materials using XANES pre-edge information, J SYNCHROTR, 8, 2001, pp. 952-954
Citations number
17
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
JOURNAL OF SYNCHROTRON RADIATION
ISSN journal
09090495 → ACNP
Volume
8
Year of publication
2001
Part
2
Pages
952 - 954
Database
ISI
SICI code
0909-0495(200103)8:<952:DOTIOS>2.0.ZU;2-3
Abstract
Fe K-edge XANES spectra have been measured in more than 35 Fe( II) and Fe(I II)-bearing minerals. The separation between the average pre-edge centroid positions for Fe( II) and Fe( III) is 1.4 +/- 0.1 eV. Examination of calcul ated pre-edge features of mechanical mixtures of phases containing differen t proportions of Fe( II) and Fe( III) reveals that different trends of pre- edge position vs. pre-edge intensity can be observed, depending on the coor dination environment. Both pre-edge parameters have been used to estimate t he ferric/ferrous ratio in 12 natural minerals.