Elements of crystallography

Teacher(s)

Filinchuk Yaroslav;

Language

French

Prerequisites

algebraic knowledge base

Main themes

• Elements of symmetry
• Crystal lattice
• One-time groups
• Space groups
• Use of International Tables of Crystallography
• Principles of diffraction, reciprocal space
• Intensity diffracted by a crystal
• Single crystal diffraction, powder diffraction Experimental methods and instruments
• Information obtained by diffraction Introduction to structural chemistry, contribution of crystallography in the knowledge of chemistry

Aims

At the end of this learning unit, the student is able to :
1	reasoned understanding (knowing how to explain) of symmetry and in particular of molecular symmetry understanding the fundamentals of modern methods of crystallographic analysis and the results they provide

Content

Symmetry

1. Introduction, molecules and crystals, elements of symmetry
2. Point groups, chirality
3. Translation, plan groups, crystal lattice, elements of periodic symmetry
4. Space Groups, International Tables of Crystallography

Methods

1. X-rays, neutrons, diffraction principles, reciprocal space
2. Structure factor, Fourier synthesis, phase problem
3. Information obtained by diffraction
4. Diffraction methods: single crystals and polycrystals (powders)
5. Resolution of structures, identification of known and unknown compounds
6. Refinement of crystalline structures
7. Presentation of modern software (CrysAlis, Fullprof, Shelx, Fox)

Results

1. Use and presentation of results, interpretation of literature data
2. Introduction to structural chemistry
3. Diffraction chemistry: in situ studies
4. The big "instruments" - synchrotrons and neutron sources: the great possibilities

Teaching methods

Due to the COVID-19 crisis, the information in this section is particularly likely to change.

The course is given with the use of PowerPoint presentations, available on moodle. The court also includes software demonstration and the use of interactive material. Exercises are planned to facilitate understanding.
exercises:

1. One-off groups
2. Networks. Groups of the plan. Slip plane
3. Space Groups
4. Practical exercises in the laboratory:

• diffraction on single crystals, powder
• Description and comparison of crystalline structures.
• Types of structure

Evaluation methods

Due to the COVID-19 crisis, the information in this section is particularly likely to change.

An oral exam with written preparation. It includes two theoretical questions with written preparation and the others without preparation (total of 15 points). The practical part is examined by the engineer, Dr. Koen Robeyns, and is evaluated with a maximum of 5 points. Students can earn one more point for creative homework.

Online resources

> https://symmetry.otterbein.edu/ - interactive guide to molecular symmetry
> https://escher.epfl.ch/mobile/ - crystallography on a mobile phone, 2D periodic groups
> https://nanocrystallography.research.pdx.edu/index.py/links - collection of useful links
> https://escher.epfl.ch/eCrystallography/ - electronic crystallography course

Bibliography

1. J.-J. Rousseau, A. Gibaud, Cristallographie géométrique et radiocristallographie (Dunod, 3e édition, 2007).
2. R. Tilley, Crystals and crystal structures (Wiley, 2006).

Faculty or entity

CHIM