[Ifeffit] Artemis

[Bruce Ravel]

On Tuesday 08 January 2008 12:34:00 Alain Manceau wrote:
> Thank you for the clarification. I progressed, but still encounter a
> problem running FEFF7. The error message and the input parameters and
> configuration are shown in the ppt in attachment.


Hi Alain,

I thought I would add a few thoughts to the very helpful feedback from
Richard, Wayne, and Michel.

I just tried artemis with feff7 and it works just fine on my computer.
I did as I said -- I pointed artemis at the feff7 executable and
changed the feff template to feff7.  Feff7 ran and it wrote out
feffNNNN.dat file which got imported properly.  So it all seems fine
to me -- although I should probably take a look-see on a windows
machine to be sure everything works the same there.

As a work-around, given the torubles you are seeing on your machine, I
would suggest doing as Richard adn Wayne suggested and run feff7
outside of Artemis then import the results.

As for the plotting question, I suspect there is not a problem, simply
a disconnect with expectation.  The numbers for k-range in the box
labeled "Fourier and fit parameters" is the k-range used whenever a
Fourier transform is made.  It is also the fit range in k.  The
k-range shown in the lower right-hand corner of the Artemis window is
the range over which the plot is made.  All arrays in k are defined
from 0 to the end of the input data range and the path arrays
certainly contain data below there as Feff starts its calculationo at
k=0.  Thus the fit array contains data below the fit range even though
the data outside that range does not contribute to the evaluation of
the fitting metric.  As Shelly Kelly often points out, if your fit
resembles your data even outside the fitting range, that is an
additional tidbit giving confidence in the appropriateness of your
fitting model.

HTH,
B


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

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