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 (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 gtgt
resonant frequency of electrons in atom
frequently not true
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Dispersion - anomalous scattering
Have assumed radiation frequency gtgt
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"
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f"
???K
1
2
f'
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Atom assemblies
(see Cowley sect. 5.1)

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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