Recently I was questioned about the EXAFS detection limit when describing different metal species in a bimetallic sample.

By checking Pd and Cu K-edges, for example, I found Pd metal nanoparticles and CuO clusters, respectively. But additional techniques tell me I can have copper atoms in intimate contact with the Pd nanoparticles. What would be the minimum amount of these "single atoms" needed to be detected by EXAFS? is there a detection limit or it depends on several parameters?

Thanks!!!
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