LEED is widely used to study of the crystal structure of single crystal surfaces in ultrahigh vacuum conditions. Information about the structure of the surface is obtained by analyzing the elastically scattered electrons by the crystal, and this leads to the conclusion about perfection of the crystal structure of the sample, the orientation of the crystallographic axes in space. This information is necessary for the proper orientation it in the right direction for further crystallographic study of dispersion of the energy bands along the preferred directions of the surface Brillouin zone with high symmetry by photoelectron spectroscopy with angular resolution (ARPES). This technique reduces the time required for characterization and orientation of single crystal surface or low-dimensional structures formed on its surface.
