How's diffraction pattern modied by phonon perturbation?

leehoom
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Hi there,
I have a problem on phonon perturbation's effect on diffraction pattern.

Assume atomic planes parallel to (100) of bcc lattice is periodically perturbed by phonon.

How will diffraction pattern be modified as a result of such perturbation? Will we see any diffraction peaks in addition to those seen for a unperturbed lattice?

Thanks!
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You get a reduction in the amplitude of the normal diffraction peaks, usually described by a Debye-Waller factor, and in addition you get Thermal Diffuse Scattering.

http://en.wikipedia.org/wiki/Debye–Waller_factor

http://www.neutron.ethz.ch/education/Lectures/neutronfall/Lecture_4-2
 
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M Quack said:
You get a reduction in the amplitude of the normal diffraction peaks, usually described by a Debye-Waller factor, and in addition you get Thermal Diffuse Scattering.

http://en.wikipedia.org/wiki/Debye–Waller_factor

http://www.neutron.ethz.ch/education/Lectures/neutronfall/Lecture_4-2
Thank you! It's really helpful.
 
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