# [Ifeffit] how to reduce the core-hole lifetime broadening in feff8.2

Bruce Ravel bravel at bnl.gov
Thu Jun 11 12:51:54 CDT 2009

On Thursday 11 June 2009 01:34:34 pm joshua jason kas wrote:
> As mentioned already, you can use the EXCHANGE card with negative values
> to reduce the core-hole broadening. Note however that this will not work
> with the CORRECTIONS card.

And yet, the documentation for the CORRECTIONS keyword says:

"The real energy shift vrcorr moves E0 in the final \chi(k) and
the imaginary energy shift vicorr adds broadening to the
result. The real energy shift is useful to correct the error in
FEFF's Fermi level estimate and the imaginary part can be used to
correct for experimental resolution or errors in the core-hole

And a couple of sentences later:

"The imaginary energy is typically used to correct for instrument
broadening or as a correction to the mean free path calculated by
feff."

Perhaps the document should be updated to explain more clearly what
CORRECTIONS actually does.

B

--

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

National Institute of Standards and Technology
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