X-ray diffraction

Definition

X-ray diffraction (XRD) is a technique used to study the atomic structure of crystalline materials by observing the patterns produced when X-rays are diffracted through them. It provides information about the arrangement of atoms and can reveal details about the crystal's lattice parameters.

5 Must Know Facts For Your Next Test

1. X-ray diffraction is based on Bragg's law, which relates the wavelength of X-rays to the angle at which they are diffracted and the distance between atomic planes in a crystal.
2. The characteristic X-ray patterns obtained from diffraction are unique to each material, allowing for identification and analysis of crystalline substances.
3. XRD can be used to determine unit cell dimensions, identify unknown crystals, and measure strain in materials.
4. The intensity of diffracted X-rays is influenced by the electron density within the crystal, providing insight into atomic positions.
5. In an XRD experiment, monochromatic X-rays (having a single wavelength) are typically used to ensure clear diffraction patterns.

Review Questions

• What fundamental principle does X-ray diffraction rely on?
• How can X-ray diffraction be used to identify a material?
• What information about a crystal can be determined using X-ray diffraction?

Related terms

Bragg's Law: A fundamental equation in X-ray crystallography that relates the wavelength of incident X-rays with the angle of incidence and spacing between crystal planes: $n\lambda = 2d\sin(\theta)$.

Crystalline Materials: Materials whose atoms are arranged in a highly ordered structure forming a repeating pattern extending in all three spatial dimensions.

Monochromatic X-rays: X-rays that consist of photons all having nearly identical energy or wavelength, simplifying analysis in experiments like XRD.