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

[Bruce Ravel]

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
    lifetime."

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

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