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One of the important corrections is for the absorption of the incident
and diffracted x-ray beams as they travel through the sample.
Three possible absorption correction methods are:
It is important to remember that the absorption signal is
different than the DAFS and signals because XAFS weights
the sites based on the number of atoms within the unit cell, whereas DAFS
weights the sites crystallographically. Thus measurements of the single
function are not sufficient to determine the multiple
and functions for systems which contain multiple inequivalent
- For small absorption corrections, intensity formula, and the
effective produced by the direct spline analysis method can be
appropriately phase shifted. This method is illustrated by the direct
spline analysis of the Cu data presented in Section 5.
- The absorption correction can be reconstructed from the simultaneous
fluorescence measurements. This method is illustrated by the iterative
Kramers-Kronig analysis of the Cu and
presented in Sections 5, 7 and 8.
- The absorption correction could also be constructed self-consistently
using the f'' functions obtained during the iterative Kramers-Kronig
analysis of the DAFS signal.