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Historical Perspective

  • Page ID
    78075
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    1912: Maxwell von Laue first discovered X-ray diffraction
    • determined that X-rays would be scattered by atoms in a crystalline solid if there was similarity in the wavelength of X-rays and the interatomic distances of the crystalline material.
    1913: Sir William H. Bragg and and his son Sir W. Lawrence Bragg derived the equation known as Bragg’s Law to define diffraction as a function of the angle of incidence
    \[\mathrm{2d \sinθ = nλ}\]
    λ = wavelength of the x-ray
    θ = scattering angle
    n = integer representing the order of the diffraction peak
    d = inter-plane distance of (i.e atoms, ions, molecules)
    • determined why the cleavage faces of crystals appeared to reflect X-ray beams at certain angles of incidence (θ). This is due to constructive interference.
    • simulated the experiment, using visible light and tiny arrays of dots and pinholes to mimic atomic arrangements on a much larger scale. These experiments provided similar patterns to X-rays but were safer to work with than X-rays.
    1914: von Laue awarded Nobel Prize for discovery of X-ray diffraction by crystals and showing X-rays are electromagnetic waves 1915: Braggs awarded Nobel Prize for their work determining the crystal structure of diamond, NaCl and ZnS.

    This page titled Historical Perspective is shared under a CC BY-NC-SA 2.5 license and was authored, remixed, and/or curated by Celeste Morris, Bradley Sieve and Heather Bullen via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.