Radiation: X-rays, neutrons and electrons

• Elastic scattering of radiation

-- No energy is lost

• The wave length of the scattered wave remains unchanged

• Regular arrays of atoms interact elastically with radiation of sufficient short wavelength as shown in Figure 6.01.

Figure 6.01: Schematic of interaction of radiation with the atom.

-- Cu-K_α X-ray radiation: λ =0.154 nm

• Scattered by electrons

• ~from sub mm regions

-- Neutron radiation λ~0.1nm

• Scattered by atomic nuclei

• Several cm thick samples

-- Electron radiation (200 kV): λ =0.00251 nm

• Scattered by atomic nuclei and electrons

• Thickness less than 200 nm