[Ifeffit] Advice on using Athena for XANES LCF on spectra with a small edge step?

[Carlo Segre]

Hi Mike:

How are you trying to fit it?  It looks to me like the post edge line is 
not in the right place.  You need to tune it by hand when you have such a 
short energy range after the edge since the normalization is critically 
dependent on how you set this line.

carlo

On Tue, 15 Jan 2019, Mike Massey wrote:

> Hi All,
>
>
> Does anyone have advice for LCF of spectra with a small edge step?
>
> I've recently found myself with more and more issues fitting spectra like the one shown in the attached photo, where the spectrum is of good quality, but the fits end up not working out due to normalization (as far as I can tell).
>
> Sadly, I have so far ended up just throwing these fits out, but I'm hoping there is a better solution out there that someone might be able to recommend.
>
> One solution is "get more of the element of interest," as a beamline scientist recently told me. I'm just reluctant to really load it up in the data collection, because at 2 keV I get nervous about artifacts like self-absorption.
>
> Is there a better way? What am I missing?
>
> Thanks for your thoughts,
>
>
>
> Mike
>
>

-- 
Carlo U. Segre -- Duchossois Leadership Professor of Physics
Interim Chair, Department of Chemistry
Director, Center for Synchrotron Radiation Research and Instrumentation
Illinois Institute of Technology
Voice: 312.567.3498            Fax: 312.567.3494
segre at iit.edu   http://phys.iit.edu/~segre   segre at debian.org