[Ifeffit] Help in background removal with Athena

[Robert Meulenberg]

To add to Fred's comments, as someone who has done a lot of soft x-ray
spectroscopy, there is simply not enough "room" above the edge to do EXAFS
at these energies.  There is a lot of competition from molecular resonances
and other light elements.  For instance, the feature around 290 eV is due
to a 1s --> sigma^* transition.  Also, the feature at ~400 eV could as
likely originate from some spurious nitrogen in your system than
photoelectron scattering.

Carbon NEXAFS is well established to look at the bonding and chemistry of
SAMs, graphene, diamond, etc.  I suggest you search that out.  Jo Stohr has
a good book on the subject (http://www-ssrl.slac.stanford.edu/stohr/).

Also, I would highly recommend getting better quality data.  Even with SLG
you should be able to count for an appreciable time to get higher quality
data.  This will reveal a lot of the resonances you see in carbon, and will
allow your angle dependent measurements to be more quantifiable.  (I assume
you are doing angle dependence to probe the orientation of the graphene on
whatever substrate you have).

Best regards,

Rob Meulenberg



-- 
Robert W. Meulenberg
Associate Professor of Physics
Laboratory for Surface Science and Technology
Department of Physics and Astronomy
University of Maine
Orono, ME 04469
phone: 207-581-2245
email: robert.meulenberg at maine.edu
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