Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups [CPC: G01N3/00] – [CPC: G01N17/00], [CPC: G01N21/00] or [CPC: G01N22/00] by using diffraction of the radiation by the materials, e.g. for investigating crystal structure; by using scattering of the radiation by the materials, e.g. for investigating non-crystalline materials; by using reflection of the radiation by the materials