A tool for determining the angle at which a beam of X-rays or neutrons will diffract off a crystalline structure is fundamental to materials science. This angle, named after William Henry and William Lawrence Bragg, is derived from the wavelength of the incident beam and the spacing between atomic planes within the crystal lattice. For example, knowing the characteristic X-ray wavelength of copper and the diffraction angle, one can calculate the interplanar spacing of a crystal.
Understanding the diffraction angle allows researchers to analyze the structure of materials, identifying phases, determining crystal orientation, and studying defects. This technique, stemming from early 20th-century work, is invaluable in fields ranging from metallurgy and semiconductor technology to pharmaceuticals and archaeology. Its application facilitates advancements in materials design and characterization.
