Neutron beams - Understanding and characterizing matter

This article presents the various methods using the wave-properties of neutrons. Many materials are crystallized and notably metals. Crystal are characterized by a particular atom pattern on an elementary mesh. This elementary mesh is the basic element which is repeated a vast amount of times in grains. When a monochromatic neutron beam meets a polycrystal or a powder, some of the grains present at least one family of planes in reflection position: a set of Debye-Scherrer cones is obtained which are a signature of the crystalline geometry.