Diffraction: from crystal to structure

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Diffraction from crystal to structure
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Bragg Diffraction
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Diffraction what is the sight of one slit
slitting?
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The Laue equations The path difference between
waves scattered by two neighboring points will be
related to the angle of incidence µ and the
angled of scattering ? by the equation
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Now the path difference between waves scattered
by two different translation directions (a and b)
each with of incidence µ and the angled of
scattering ? gives two equations and two integers
(what will become Miller indices for three
dimensional gratings crystals)
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Or regard n as an overtone of the primary
scattering (interplanar spacing of d/n) then n
drops out of the equation.
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?
?
?
The optical diffraction of monochromatic,
coherent (laser) light from a 1 or 2 dimensional
grating (Fraunhofer diffraction) is directly
analogous to X-ray diffraction by crystals (Laue
or Bragg diffraction). Note that this is the
same as the previous Laue equations, with µ
(incident) 90, ? (scattered) 90-f.