In the kinematic scattering limit, the measured DAFS intensity is
proportional to the square of the unit cell structure factor, , times an x-ray absorption correction factor,
,
The x-ray absorption correction factor for a symmetric Bragg reflection
from a sample of thickness t is given by . Note that absorption
produces additional fine structure in the measured DAFS intensities due to
the XAFS modulation of the x-ray absorption coefficient,
.
There are both real and imaginary x-ray scattering contributions to the
DAFS oscillations which come from the individual atomic
contributions to the unit cell structure factor,
To keep the notation compact, we include the anisotropic diffraction
Debye-Waller factors implicitly in our notation: for example,