[Ifeffit] fitting

[Bruce Ravel]

On Thursday 13 May 2010, 05:21:02 pm, mohamed sobhy wrote:

> Dear all
> I am trying to use artemis to do fitting to CeO2. But really I cant get the
>  right way to do that. During the fitting, I am using amp as set and change
>  in N degeneracy of the path. attached is the best fit i got but it still
>  not good and the chi-square is 41.109065479 so can you suggest me what to
>  do

Mohamed,

I think you need to do some homework.

Along with Shelly's suggestion, I suspect that you need to read up on the 
meaning of the Rbkg parameter in Athena.  There is some discussion of this in 
the Athena manual.  Shelly's book chapter is very useful.

I suggest you also read up on what's been written about how to interpret chi-
square.  Look through the stuff at xafs.org.  Matt, Shelly, and Scott -- as 
well as myself and others -- have written extensively about how to think about 
chi-square.  It is not obvious just from looking at a picture that there is 
anything wrong with your fit.

B

-- 
 Bruce Ravel  ------------------------------------ bravel at bnl.gov

 National Institute of Standards and Technology
 Synchrotron Methods Group at NSLS --- Beamlines U7A, X24A, X23A2
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