On Mon, 2011-10-31 at 15:57 +0000, Ivan Shabalin wrote:
> As a result, red peeks around Se are significantly lower, Se B-factors are a bit smaller (like 25.6 and 23.1), and Rf is lowered by a bit more than 0.1% with the same input files.
Hope others will comment to clarify my confusion:
It seems that the potential effect of correcting the structure factor
data depends strongly on how close to the edge you are:
The reduction of the overall scattering factor has a steep wavelength
dependence. For example, the Se atom has 34 electrons, so that should
be a rough estimate of its scattering factor in the absence of
absorption. At the very edge, f'~-8 electrons, which seems equivalent
to the ~80% occupancy, or the difference density peak on par with that
of a water molecule. I guess it's also true that close to the edge you
will have more damage, thus the negative density.
Other words, is it possible that Ian (and others) do not see a
significant effect from correcting the scattering factors because they
do not collect close to the edge, while Ivan might have done exactly
that?
Cheers,
Ed.
--
After much deep and profound brain things inside my head,
I have decided to thank you for bringing peace to our home.
Julian, King of Lemurs
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