X-ray diffraction (XRD)

Information obtained

  • Identification of crystalline phases
  • Quantification of minerals in polycrystalline materials
  • Information about crystal structure: position of atoms, unit cell dimension
  • Information about average dimension for crystals less than 1 µm.

Principle

The technique exploits the phenomenon of diffraction, which is a result of constructive interference of photons (Figure). When photons interact in a crystal structure, they scatter from the electrons of each atom. Where there is constructive interference, diffraction occurs.

xrd_bragg
Illustration of Bragg diffraction (from physik2.uni-goettingen.de/research /2_hofs/methods/ARD)[/captio
Tech_XRPD_inside
The diffractometer avaliable in the NanoGeo Lab