Syllabus
Crystallography in Earth Sciences:
- historical introduction, platonic polyhedrons, crystallography in Earth Sciences
Structural crystallography - basic conceptions:
- definition of crystal, crystal lattice, crystal structure, point symmetry elements, symmetry restrictions due to the lattice periodicity, point groups, crystal systems,
Laue classes, Bravais lattices, Miller and diffraction index, interplanar spacing
Space groups:
- screw axis glide planes, space groups, International Tables for Crystallography, asymmetric unit, multiplicity, special and general positions
Theory of diffraction:
- reciprocal lattice, scattering by atoms, structure factor, Friedel law, Bragg equation,
Laue equations, systematic absences
The diffraction of X-rays by crystals:
- X-ray sources, Ewald construction, data collection techniques for single crystals
(Laue method, rotation method, precession camera, single-crystal diffractometer) data collection techniques for polycrystalline material, interpretation of powder patterns, Rietveld method, solution and refinement of crystal structures, neutron diffraction, electron diffraction
Annotation
The students learn about 3D symmetry elements, lattices and space groups as a starting point for understanding the distributions of atoms in real crystal structures. Basic equations describing diffraction are mentioned. Diffraction techniques that are the source of data used for structure determination are explained by means of the Ewald construction.
C. Giacovazzo (ed): Fundamentals of Crystallography, IUCr Oxford University Press, 2000