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USGS · 70019392

XAFS studies of Pb(II)-chloro and Hg(II)-chloro ternary complexes on goethite

J.R. Bargar·Petra Persson·Gordon E. Brown
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Abstract

EXAFS spectroscopy was used to study Pb(II) and Hg(II) adsorption complexes on goethite (α-FeOOH) in the presence of Cl - . At pH 7, the dominant Pb(II) species are bonded to edges of FeO 6 octahedra and are similar to complexes that occur in the absence of Cl - . At pH≤6, Pb(II)-chloro ternary complexes pedominate and are bonded to corners of FeO 6 octahedra. At pH 6.5, linear Hg(OH)Cl ternary complexes predominate that are bonded to goethite through surface oxygens in a bent Hg-O-Fe geometry. In the absence of Cl - , the Hg(II) surface complexes retain this basic geometry, but an OH group replaces the chloride ion in the first coordination shell.

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Journal De Physique. IV : JPArticle

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BibTeXRIS

J.R. Bargar, Petra Persson, Gordon E. Brown. 1997. XAFS studies of Pb(II)-chloro and Hg(II)-chloro ternary complexes on goethite. https://doi.org/10.1051/jp4%3A1997249

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