Chemistry Why Do Sulfurous Compounds Show Different Peaks in X-ray Absorption Spectra?

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Sulfurous compounds exhibit different peaks in X-ray absorption spectra due to variations in oxidation states and molecular configurations. The discussion highlights confusion regarding sodium thiosulfate, which shows two main peaks attributed to sulfur atoms in different oxidation states (-1 and +5). In contrast, magnetite only shows one peak despite having iron in multiple oxidation states (+2 and +3). This discrepancy raises questions about the relationship between oxidation states and spectral peaks. Further clarification on the interpretation of these spectra is sought, particularly regarding the behavior of thiosulfate compared to iron compounds.
feelice
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Homework Statement
Interpretation of X-ray absorption spectra
Relevant Equations
none
Hey guys :)

actually my homework was just to research the absorption spectra of some iron compounds and some sulfurus compounds - to which I have the answer. I just dont understand it. In this arcticle, fig 2b: "Phase Composition of Iron Oxide Nanoparticles Studied Using Hard X-ray Absorption Spectroscopy" the needed FeO, hematite and magnetite are listet. It was explained to the course, that roughly the oxidation state is added to the shift of the Fe-K-absorption edge which fits, also that tetrahedral conformation will lead to a pre peak, which also fits.
Now we come to the sulfurous compounds. In this article, fig.3b: "In Situ Analysis of Sulfur Species in Sulfur Globules Produced from Thiosulfate by Thermoanaerobacter sulfurigignens and Thermoanaerobacterium thermosulfurigenes", the sodium thiosulfate is somehow not fitting in for me. Why does ist have two main peaks - if you say because on sulfur has the oxidation state -1 and the other plus 5, then why does magnetite only have on peak even though it has one iron in oxidation stat +2 and the other two in +3. Why do we split in thiosulfate?

It really bothers me and I would be very glad if someone could help me solve this puzzle.
 
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feelice said:
Homework Statement: Interpretation of X-ray absorption spectra
Relevant Equations: none

In this arcticle, fig 2b:

do you have links to the 2 articles you are reading, please
 
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