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The DAFS kinematic unit cell structure factor

In the kinematic scattering limit, the measured DAFS intensity is proportional to the square of the unit cell structure factor, tex2html_wrap_inline1494, times an x-ray absorption correction factor, tex2html_wrap_inline1496,

The x-ray absorption correction factor for a symmetric Bragg reflection from a sample of thickness t is given by tex2html_wrap_inline1500. Note that absorption produces additional fine structure in the measured DAFS intensities due to the XAFS modulation of the x-ray absorption coefficient, tex2html_wrap_inline1502.

There are both real and imaginary x-ray scattering contributions to the DAFS oscillations which come from the individual atomic tex2html_wrap_inline1504 contributions to the unit cell structure factor,

To keep the notation compact, we include the anisotropic diffraction Debye-Waller factors implicitly in our tex2html_wrap_inline1506 notation: for example,