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Crystal truncation rods in kinematical and dynamical x-ray diffraction theories

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 نشر من قبل Vladimir Kaganer
 تاريخ النشر 2007
  مجال البحث فيزياء
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Crystal truncation rods calculated in the kinematical approximation are shown to quantitatively agree with the sum of the diffracted waves obtained in the two-beam dynamical calculations for different reflections along the rod. The choice and the number of these reflections are specified. The agreement extends down to at least $sim 10^{-7}$ of the peak intensity. For lower intensities, the accuracy of dynamical calculations is limited by truncation of the electron density at a mathematically planar surface, arising from the Fourier series expansion of the crystal polarizability.



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