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Fourier transform (see Cowley Sect. 2.2)
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Fourier transform (see Cowley Sect. 2.2)
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Fourier transform (see Cowley Sect. 2.2)
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Fourier transform (see Cowley Sect. 2.2)
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Fourier transform
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Fourier transform
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Fourier transform
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Fourier transform
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Scattering of x-rays by single electron (Thomson)
(see Cowley sect. 4.1)
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Scattering of x-rays by single electron (Thomson)
(see Cowley sect. 4.1)
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Scattering of x-rays by single electron (Thomson)
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Scattering of x-rays by single electron (Thomson)
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Scattering of x-rays by single atom
For n electrons in an atom, time-averaged electron density is
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Scattering of x-rays by single atom
For n electrons in an atom, time-averaged electron density is Can define an atomic scattering factor
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Scattering of x-rays by single atom
For n electrons in an atom, time-averaged electron density is Can define an atomic scattering factor For spherical atoms
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Scattering of x-rays by single atom
Need to find (r) …. A QM problem But soln for f() looks like this (in electron scattering units)
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Dispersion - anomalous scattering
Have assumed radiation frequency >> resonant frequency of electrons in atom … frequently not true
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Dispersion - anomalous scattering
Have assumed radiation frequency >> resonant frequency of electrons in atom … frequently not true Need to correct scattering factors f = fo + f' + i f"
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Dispersion - anomalous scattering
Need to correct scattering factors f = fo + f' + i f" 5 f" 1 2 K f'
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Atom assemblies (see Cowley sect. 5.1)
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For this electron density, there is a Fourier transform
Atom assemblies (see Cowley sect. 5.1) For this electron density, there is a Fourier transform F(u) is a fcn in reciprocal space
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Atom assemblies (see Cowley sect. 5.1)
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Atom assemblies
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Atom assemblies For single slit, width a & g(x) = 1 If scatterer is a box a, b, c
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Atom assemblies For single slit, width a & g(x) = 1 If scatterer is a box a, b, c For periodic array of zero-wiidth slits
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Atom assemblies This requires ua = h, an integer. Then Finally
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Atom assemblies This requires ua = h, an integer. Then Finally
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