A new theory for X-ray diffraction

  title={A new theory for X-ray diffraction},
  author={Paul F. Fewster},
  journal={Acta Crystallographica. Section A, Foundations and Advances},
  pages={257 - 282}
  • P. Fewster
  • Published 27 March 2014
  • Chemistry, Medicine
  • Acta Crystallographica. Section A, Foundations and Advances
By considering the scattering distributed throughout space, there is an intensity enhancement at the Bragg angle even when the Bragg condition is not satisfied. This leads to an alternative explanation for the diffraction from powders and small crystals. 
Comments on A new theory for X-ray diffraction
  • Jack T. Fraser, J. Wark
  • Materials Science, Medicine
    Acta crystallographica. Section A, Foundations and advances
  • 2018
This article demonstrates that this theory of X-ray diffraction is in error, and that small crystallites will give rise to scattering at angles of exactly twice the Bragg angle, whatever their orientation.
Estimating the structure factors in X-ray diffraction
  • P. Fewster
  • Medicine, Chemistry
    Acta crystallographica. Section A, Foundations and advances
  • 2018
The meaning of the structure factor and how it impacts on the determination of structures are reassessed. A route to obtaining the structure factors is presented for several data collection methods
Bragg scattering from a random potential
A potential for propagation of a wave in two-dimension is constructed from a random superposition of plane waves around all propagation angles. Surprisingly, despite the lack of periodic structure,
What is an ‘ideally imperfect’ crystal? Is kinematical theory appropriate?
  • P. Fewster
  • Mathematics, Medicine
    Acta crystallographica. Section A, Foundations and advances
  • 2016
The diffraction from imperfect crystals and the applicability of kinematical theory are described.
Response to Fraser & Wark’s comments on A new theory for X-ray diffraction
  • P. Fewster
  • Chemistry, Medicine
    Acta crystallographica. Section A, Foundations and advances
  • 2018
In response to the comments by Fraser & Wark, experimental evidence and an explanation of the new theory in the context of a modified Ewald sphere construction are presented.
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