Powder X-Ray Diffraction (PXRD)
AMI uses a Bruker D2 Phaser for powder x-ray diffraction.
While it is called "powder," what we're really testing is a polycrystalline material as opposed to a single crystal. The powder is a collection of many, many, very small crystals, referred to as crystallites. PXRD is a powerful technique for the identification of crystalline phases in polycrystalline materials. The sample is exposed to a monochromatic x-ray beam, and the intensity of the diffracted x-rays are measured as a function of the scattering angle (2Θ). Each crystalline phase of a material produces a unique “fingerprint” pattern, which can usually be identified by comparison to a database of known powder patterns. In mixtures, minor components can also be identified down to about 5% of the bulk material. For samples with very small crystallites, the width of the x-ray scattering lines yields information on the crystallite size.
PXRD can tell you: structure, crystallinity, and phase composition. It can be used qualitatively and quantitatively: what is the material I'm analyzing and how much of each material do I have? PXRD can also differentiate between the same chemical formula, but different crystal structures like quartz, cristobalite, and silica gel.
Example applications include phase identification in most solids and thin-film samples, including minerals, inorganic materials, ceramics, metal alloys, and organic materials, and the determination of the percent crystallinity in fibers, polymers, plastics, and glasses.
| Specifications | |
| Radiation Source | Cu Kα |
|
Sample capacity: |
0.5 - 2.0 g |
| 2-Theta | 3° - 135° |
| Step Width | 0.01° to 0.05° |
| Step Increment | 0.01° to 0.05° per step |
| Step Time | 0.1 to 1.0 s/step |
