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Bragg diffraction - How to make sense of it ?

  1. Jan 25, 2014 #1
    Bragg diffraction - How to make sense of it ??

    Is there a way to make sense of Diffraction of X Rays without taking recourse to oversimplified concepts like "Reflection of X Rays by parallel planes" which is generally the explanation in most basic physics books. It's been a couple years since I first studied it and i continue to get confused by assertions like reflecting of Photons by atoms. Online sources are also full of it :

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  3. Jan 25, 2014 #2


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    You can start with the Laue equations, which are derived from interference principles used in gratings, and derive the Bragg equation from them: http://www.phys.utk.edu/courses/Fall 2009/physics671/chapter1c.pdf

    Or you can start with the fully quantum mechanical Bloch theorem and derive the Bragg equation:
    http://www.uni-tuebingen.de/meso/ssscript/blochelectrons.pdf [Broken]

    But the Bragg equation is very simple, and very accurate, so I have used it extensively in my electron diffraction work.
    Last edited by a moderator: May 6, 2017
  4. Jan 26, 2014 #3
    I get that. But, is there a way to explain things without relying on mathematical formalism. I mean a general discussion on the physical mechanism.
  5. Jan 26, 2014 #4


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    Read chapter two of this dissertation: http://hdl.handle.net/2027.42/63758

    It starts with crystal theory, atomic scattering, and elastic scattering from crystals ... in short, a derivation of diffraction patterns starting from scratch.
  6. Jan 27, 2014 #5
    This article by P. P. Ewald, one of the founding fathers of x-ray diffraction, give an excellent overview without excessive math.

  7. Feb 5, 2014 #6
    Thanks for the link. If you have access, could you pls give me the pdf ?
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