ABSTRACT
Temperature, magnetic fields, pressure, processing and many other factors can affect the crystal structure. Understanding the crystal structure using diffraction techniques therefore is essential. Need of understanding diffraction techniques, what information they can reveal should be known. Commercial diffractometers today may appear more complicated due to additional slits/collimators used to improve the quality of diffraction patterns. Like in X-ray diffraction, electron diffraction also needs long-range periodicity of atoms on the surface. Similar to X-ray diffraction from a periodic lattice, which occurs following Bragg condition, neutron diffraction also occurs due to interference of elastically scattered waves of neutrons from nuclei. Elastically scattered X-rays of the same wavelength as incident wavelength of X-rays are of interest in diffraction experiments. A very simple geometrical diffraction condition was proposed by W. H. Braggs in 1912, immediately after Max von Laue observed the diffraction of copper sulphate single crystal.
