When polycrystalline samples are irradiated with X-rays a characteristic diffraction pattern results. These Debye-Scherrer reflections are photographed and then evaluated.
Tasks
- Debye-Scherrer photographs are to be taken of powdered samples of sodium chloride and caesium chloride.
- The Debye-Scherrer rings are to be evaluated and assigned to the corresponding lattice planes.
- The lattice constants of the sample materials are to be determined.
- The number of atoms in the unit cells of each sample are to be determined.
Learning objectives
- Crystal lattices
- Crystal systems
- Reciprocal lattice
- Miller indices
- Structure amplitude
- Atomic form factor
- Bragg scattering