Open AccessDetermination of the iron oxidation state in Earth materials using XANES pre‐edge information
Author(s) -
Petit PierreEmmanuel,
Farges François,
Wilke Max,
Solé Vincente Armando
Publication year - 2001
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049500021063
Subject(s) - xanes , ferrous , oxidation state , enhanced data rates for gsm evolution , k edge , analytical chemistry (journal) , earth (classical element) , spectral line , materials science , ferric , ferric iron , chemistry , inorganic chemistry , metallurgy , physics , environmental chemistry , computer science , metal , telecommunications , astronomy , mathematical physics
Fe K‐edge XANES spectra have been measured in more than 35 Fe(II) and Fe(III)‐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 calculated pre‐edge features of mechanical mixtures of phases containing different 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 coordination environment. Both pre‐edge parameters have been used to estimate the ferric/ferrous ratio in 12 natural minerals.