Open AccessManganese speciation in Diplodon chilensis patagonicus shells: a XANES study
Author(s) -
Soldati A. L.,
Goettlicher J.,
Jacob D. E.,
Vilas V. Vicente
Publication year - 2010
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/s090904950905465x
Subject(s) - xanes , manganese , genetic algorithm , absorption (acoustics) , shell (structure) , oxidation state , chemistry , extended x ray absorption fine structure , analytical chemistry (journal) , spectroscopy , metal , absorption spectroscopy , environmental chemistry , materials science , biology , physics , ecology , quantum mechanics , composite material , organic chemistry
X‐ray absorption near‐edge spectroscopy (XANES) at the Mn K ‐edge was used to investigate the environment of Mn in situ within the growth increments of the long‐lived freshwater bivalve species Diplodon chilensis patagonicus . Single XANES spectra and Mn K α fluorescence distributions were acquired at submillimetre resolution (up to 100 µm × 50 µm), at Mn concentrations below the weight percent range (100–1000 µg g −1 ) in a high Ca matrix. The position and intensity of the pre‐edge feature in the shell spectrum resembles best that of the Mn(II)‐bearing reference compounds, suggesting that this is the oxidation state of Mn in the bivalve shells. By comparison with the XANES spectra of selected standard compounds, hypotheses about Mn speciation in the shell are also reported. In particular, different factors, such as provenance, ontogenetic age, variable Mn‐concentrations or seasonal shell deposition seem not to influence the speciation of the metal in this bivalve species.