X-ray diffraction (XRD) is a technique used to determine the crystal properties of a material by analyzing its X-ray diffraction pattern, also known as a diffractogram. This pattern represents the angular distribution of reflected X-ray emission intensity. An X-ray diffractometer, equipped with an X-ray source, a detector, and a high-precision positioning system (goniometer), records the diffractogram.
The analyzed diffractogram reveals information about the atomic arrangement in crystalline substances. This information facilitates the determination of phase content—both qualitative and quantitative—and the estimation of crystal defects, residual strain, and other properties.
It is important to note that XRD is specifically suited for the direct investigation of crystalline substances, wherein atoms are arranged in periodically repeating structures.
On the other hand, the predominance of crystalline substances among solids—such as metals, rocks, building materials, and medicines—underscores the widespread applicability of XRD across various industries and scientific fields.
These fields include the study of crystalline properties of new materials, determination of phase composition in the mining industry, control of parameters in the production of pharmaceuticals, building materials, and metallurgical products, and forensic analysis.
A diffractometer can be utilized to analyze various types of crystalline samples, as well as samples with a mixture of amorphous phases, including powdered materials, polycrystalline films, bulk pieces, etc. Below are some examples of sample types that can be analyzed using a diffractometer:
X-ray methods have been among the most powerful and versatile instruments in scientific research, medicine, and technology for over a century. The unique properties of X-ray radiation make it possible to carry out non-destructive diagnostics, introspection, to detect certain types of substances and to investigate their properties. It can be said that since the wavelength of X-rays is comparable to the characteristic distance of interatomic bonds, it allows us to look deep into matter.
One of the main and widely sought-after areas of X-ray research is X-ray crystallography analysis, which answers basic questions about the crystal structure of matter and its properties. X-ray diffractometry is an effective method of X-ray crystallography analysis.
