Dear Fernando,

you may use XANES spectroscopy.

However I fear that for the determination of the oxide state of your dopands the concentration of them might be too small.

How thick is your organic layer and which metalls you are thinking on?

https://www-ssrl.slac.stanford.edu/conferences/workshops/srxas2011/presentations/sarangi_xanes_2011.pdf

Dear Gerhard,

thanks for your answer. We have particles with a core size about 3 nm and the organic layer is about 10 nm. Regarding metals; Ni, Cu, Zn and Mn

thanks

F. 

The K-edges of your  metall atoms are easily accessable and the 10nm organic layer ís no challenge for the x-rays. Core size is no problem but the overall concentration could be too small.

However using a synchrotron as x-ray source could help.

Please have a look at the link.

You 'adress' your metal dopands via the k-edge energy. But therefore it is necessary to have no further Ni, Cu, Zn or Mn in your sample or in the sample support.

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