Re: Feff8.2 Xanes edge energy seems to be off +9ev

[Bruce Ravel <ravel@phys.washington.edu>]

On Tuesday 07 September 2004 09:55 am, Eric Breynaert wrote:
> Dear feff_users,
>
> I'm relatively new at feff. I'm trying to calculate the xanes edge for
> pertechnetate with feff8.2. This version of feff seems to calculate the
> pre-edge of pertechnetate quite well and the shape of the xanes edge also
> seems ok, but the energy of the edge seems to be off +9eV from our
> experimental data. I'm including the feff.inp i used as an
> attachment.  Does anyone have a clue what happens?

In my experience Feff does a fine job of computing energy on a
relative scale, but not so great on an absolute scale.  If you are
happy with the shape of the calculated spectrum, you should just shift
it by those 9 eV and declare victory.

Here are a couple of old posts by John which say the same:

   http://cars9.uchicago.edu/feff/feffusers/msg00094.html
   http://cars9.uchicago.edu/feff/feffusers/msg00164.html

B

-- 
 Bruce Ravel  ----------------------------------- ravel@phys.washington.edu
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