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