[Ifeffit] Vanadium pre edge peak contributes to K-space?

[Bruce Ravel]

On Tuesday 25 August 2009 11:02:26 am Chris Patridge wrote:
> Hello all,
>
> After calibration, alignment and merging V K edge data, there seems to
> be a large peak in R space below 1 A.  From most examples and readings,
> this would seem to be noise since atoms do not reside that close to each
> other.  Adding a background addresses this noise but then the number of
> variables becomes too large and meaningless to the first shell R space
> range.  I believe the problem lies with the large pre edge feature seen
> with high valence state Vanadium compounds.  Any suggestions on how to
> work through this and make realistic EXAFS analysis on these compounds.
>
> Thanks everyone,


Didn't Richard Mayes answer this same question from you last month?

   http://millenia.cars.aps.anl.gov/pipermail/ifeffit/2009-July/004365.html

In my experience, Richard's answer was spot on for V K edge data.

If Richard's good advice didn't help, then you need to be more
explicit about what the problem is, perhaps by posting a small athena
project file that demonstrates the problem.

B


-- 

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

 National Institute of Standards and Technology
 Synchrotron Methods Group at NSLS --- Beamlines U7A, X24A, X23A2
 Building 535A
 Upton NY, 11973

 My homepage:    http://xafs.org/BruceRavel
 EXAFS software: http://cars9.uchicago.edu/~ravel/software/exafs/