[Ifeffit] Warning "e0 is greater than 10"

[Carlo Segre]

Hi Ke

Yes, if you change the position of your E0 in Athena, it will result in a
shift in your fit parameters.  However, don't simply shift your E0 just to 
avoid the warning.  Take a look to see if Athena mispositioned it first 
but if you are confident that it is correct, then you might take a look to 
see if E0 is large because you are not using a good model to fit the data. 
E0 is highly correlated with the path lengths so if you are way off in the 
latter, it can have an effect on E0.

carlo


On Tue, 14 Oct 2014, Ke Yuan wrote:

> Hello Feff community,
>
> I am practicing on using Artemis to fit a UO2 XAFS data I measured. The
> parameters I used can be found from the pic attached. The Artemis project
> file is also attached.
>
> I have been getting this "e0 greater than 10" warning on many of my
> fittings. Will picking a slightly different E0 change the result much? Any
> suggestions on how to improve this fitting?
>
> Thanks!
> Ke
>
>

-- 
Carlo U. Segre -- Duchossois Leadership Professor of Physics
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