A study on the limit of application of kinematical theory of X-ray
diffraction
ZEITSCHRIFT FUR KRISTALLOGRAPHIE-CRYSTALLINE MATERIALS, 235 (11):
523-531 (2020)DOI: 10.1515/zkri-2020-0035
Abstract
In this work, the limit of application of the kinematical theory of
X-ray diffraction was calculate integrated intensities was evaluated as
a function of perfect crystal thickness, when compared with the
Ewald-Laue dynamical theory. The percentual difference between the
dynamical and kinematical integrated intensities was calculated as a
function of unit cell volume, Bragg angle, wavelength, module, and phase
of structure factor and linear absorption coefficient. A critical
thickness was defined to be the value for which the intensities differ
5%. We show that this critical thickness is 13.7% of the extinction
length, which a specific combination of the parameters mentioned before.
Also, we find a general expression, for any percentage of the difference
between both theories, to determine the validity of the application of
the kinematical theory. Finally, we also showed that the linear
absorption decreases this critical thickness.