The method reveals the structure and function of many biological molecules, including vitamins, drugs, proteins and nucleic acids such as DNA. Using X-ray diffraction, one may determine the three-dimensional atomic structure in chemical compounds, materials and proteins.
X-Ray Crystallography uses the uniformity of light diffraction of crystals to determine the structure of a molecule or atom. Then they use an X-ray beam to “hit” the crystallized molecule. The electrons surrounding the molecule diffract as the X-rays hit them. This forms a pattern is called the X-ray diffraction pattern.
The 3-dimensional atomic structure is the basis for understanding for example material behavior or reaction mechanisms in enzymes. The combination of crystallography with other methods is the key to understand, improve and manipulate materials.
Three different powder X-ray diffractometers are available.
- A fixed-stage STOE diffractometer with a curved IP-detector and a Cu source can be used for fast phase-identification of powder samples.
- For more detailed and/or specialised studies a pair of Rigaku SmartLab diffractometers are available for powders as well as bulk samples. These very versatile and high-resolution diffractometers use high-intensity rotating anode X-ray sources (Cu and Co respectively).
- Specific sample environments are available allowing for a wide range of experiments to be performed including e.g. raster scanning and temperature studies in the range 12-1000 K.
A number of single crystal diffractometers are also available including an Oxford Diffraction Supernova instrument equipped with a four-circle kappa goniometer, an Atlas charge-coupled device detector, a Mo microfocus X-ray source, and an Oxford Cryosystems Cryostream device enabling temperatures in the range 100-450 K. Furthermore, Cu and Ag silver X-ray sources are available and the setups can fit diamond anvil cells for high-pressure experiments.
Total scattering experiments are carried out at synchrotron facilities around the world. Total scattering and pair distribution function (PDF) analysis enable studies of defects and deviations from the average crystal structure, containing both crystalline and amorphous phases.