Braggdiffraksjon

Braggdiffraksjon, also known as X-ray diffraction (XRD), is a phenomenon that occurs when X-rays interact with a crystalline material. The regular arrangement of atoms within a crystal lattice acts like a three-dimensional diffraction grating. When X-rays strike these planes of atoms, they are scattered. If the scattered waves are in phase, they interfere constructively, leading to a diffracted beam.

The conditions for constructive interference are described by Bragg's law, which states that nλ = 2d sin(θ). Here, n is an integer representing the order of diffraction, λ is the wavelength of the X-rays, d is the spacing between the atomic planes in the crystal, and θ is the angle of incidence of the X-rays relative to the crystal planes. This law is fundamental to understanding and analyzing diffraction patterns.

When a beam of X-rays impinges on a crystalline sample, a set of diffracted beams emerges at specific angles determined by the crystal structure and the X-ray wavelength. By measuring the angles and intensities of these diffracted beams, one can deduce information about the crystal's atomic arrangement, including the size and shape of the unit cell, the positions of atoms within the unit cell, and the presence of different crystalline phases. Braggdiffraksjon is a powerful, non-destructive technique widely used in materials science, chemistry, physics, and mineralogy for identifying and characterizing crystalline substances.