X-ray scattering techniques

This is an X-ray diffraction pattern formed when X-rays are focused on a crystalline material, in this case a protein. Each dot, called a reflection, forms from the coherent interference of scattered X-rays passing through the crystal.

X-ray scattering techniques are a family of non-destructive analytical techniques which reveal information about the crystal structure, chemical composition, and physical properties of materials and thin films. These techniques are based on observing the scattered intensity of an X-ray beam hitting a sample as a function of incident and scattered angle, polarization, and wavelength or energy. Note that X-ray scattering is different from X-ray diffraction, which is widely used for X-ray crystallography.

Scattering techniques

Elastic scattering

Materials that do not have long range order may also be studied by scattering methods that rely on elastic scattering of monochromatic X-rays.

• Small-angle X-ray scattering (SAXS) probes structure in the nanometer to micrometer range by measuring scattering intensity at scattering angles 2θ close to 0°.
• X-ray reflectivity is an analytical technique for determining thickness, roughness, and density of single layer and multilayer thin films.
• Wide-angle X-ray scattering (WAXS), a technique concentrating on scattering angles 2θ larger than 5°.

Inelastic scattering

When the energy and angle of the inelastically scattered X-rays are monitored, scattering techniques can be used to probe the electronic band structure of materials. Inelastic scattering alters the phase of the diffracted x-rays, and as a result do not produce useful data for x-ray diffraction. Rather, inelastically scattered x-rays contribute to the background noise in a diffraction pattern.

• Compton scattering
• Resonant inelastic X-ray scattering (RIXS)
• X-ray Raman scattering

See also

• Structure determination
• Materials science
• Metallurgy
• Mineralogy
• X-ray crystallography
• X-ray generator
• Ultrafast x-rays

References

External links

Wikimedia Commons has media related to X-ray diffraction.

• Learning Crystallography
• International Union of Crystallography
• IUCr Crystallography Online
• The International Centre for Diffraction Data (ICDD)
• The British Crystallographic Association
• Introduction to X-ray Diffraction at University of California, Santa Barbara