Topics List

We are now accepting submissions to the AVL.  Suggested video topics are below but creators are encouraged to submit videos on topics not included:

Overview for Non-Crystallographers

1. Historical perspective (see https://www.iycr2014.org/learn/watch)
2. Crystallization/ what can we glean?
3. How to grow a good crystal
4. Visual inspection
5. Size, shape, crystallinity
6. General confirmation of synthetic process
7. Three-Dimensional picture of your molecule in the solid state
8. Connectivity   
9. Stereochemistry
10. Packing considerations
11. Bonds, angles, torsions
12. Intermolecular interactions
13. Hydrogen bonding
14. Pi-stacking
15. Void spaces
16. Diffraction assessment
17. Well-formed reflections, high resolution, proper instrument
18. Unit cell check
19. Known compound, realistic parameters
20. Data collection
21. Data integration / processing
22. Proper symmetry, scaling and corrections
23. Structure solution
24. Structure refinement
25. Structure Validation (PDB, CCDC)
26. Final report
27. Impact

What You Can Glean from Your XRD Data

1. General confirmation of synthetic process
2. Three-Dimensional picture of your molecule in the solid state
3. Connectivity   
4. Stereochemistry
5. Packing considerations
6. Bonds, angles, torsions
7. Intermolecular interactions
8. Hydrogen bonding
9. Pi-stacking

How to Publish XRD Results

1. Prepare your CIF file
2. Use CheckCIF to validate the CIF file 
3. Make sure all A-Alerts are answered/corrected
4. Include information about refinement issues/modeling of structure
5. Submit CIF file to journal or CCDC according to author instructions
6. Make sure data quality is appropriate for target publication
7. Include experimental details in manuscript or supporting information as needed
8. Include ORTEP of structure in S.I.
9. Consideration for appropriate Figures for publication

Theory

1. Data Collection
   1. Diffraction Geometry
      1. Bragg’s Law
      2. Laue equations
      3. Ewald sphere
      4. Four circle (serial detectors) and rotation (area detectors) geometry
      5. Friedel’s Law
   2. Intensity Data Collections
      1. Unique data
      2. Redundancy
      3. Equivalent reflections
      4. Selection and accuracy of data
      5. Integrated Intensities
   3. Data Reduction
      1. Corrections
         1. Lorentz and polarization
         2. Absorption
         3. Crystal degradation
         4. Scaling
   4. Structure Factors and Fourier Synthesis
      1. Waves, vectors, and complex numbers
      2. Superposition of waves
      3. Structure factors
      4. Fourier synthesis
      5. Anomalous scattering
      6. The phase problem
   5. Structure Solution
      1. Direct methods
      2. Heavy atom methods
      3. Charge Flipping methods
2. Diffraction
   1. X-ray scattering from electrons, atoms, unit cells, and crystals
   2. The structure factor equation
   3. The electron-density equation
   4. Miller Planes
   5. Bragg’s law
   6. Resolution
   7. The phase problem
3. Symmetry - Crystal and Lattice
   1. 7 Crystal systems
   2. 14 Bravais Lattices
   3. Unit cells
   4. Asymmetric units
   5. Direct and reciprocal lattices
4.  Space Group Symmetry
   1. Herman-Mauguin and Schönflies notation
   2. Symmetry operators – inversion, rotation, improper rotation, mirror planes, screws axes, and glide planes
   3. Generating space group tables
   4. General and special positions
   5. Interpreting entries from the International tables entries

Applied

1. Crystal Growth Techniques
   1. Evaporation, slow cooling, vapor diffusion, solvent diffusion, convection, sublimation, etc.
   2. Solvent selection
2. Crystal Screening
   1. Size, shape, and general appearance
   2. Crystal mosaicity
   3. Polarizing microscopy
   4. Unit cell determinations
3. Crystal MountingMounting air-sensitive materials
   1. Goniometer heads
   2. Mounts
   3.  Fiber/adhesive, loops, micromounts, etc.
4. Crystallographic Databases
   1. Contents
   2. Search methods and strategies
5. Data Collection
   1.  Indexing
   2. Counting Statistics
   3. Data quality and limitations
   4. Low temperature and room temperature data
   5. Unique Data
   6. Redundancy
6. Space Group Determination
   1. Metric symmetry and Laue symmetry
   2. Unit cell contents
   3. Lattice centering
   4. Systematic absences
   5. Systematic distribution of intensities
7. Structure Solution and the Phase Problem
   1. Direct methods
   2. Heavy atom methods
   3. Charge Flipping methods
8. Structure refinement
   1. Least-squares refinement
   2. Difference Fourier synthesis
   3. Atomic displacement parameters
   4. Hydrogen atoms
9. X-ray generation
   1. Sealed tube, rotating anode, synchrotron, and X-ray optics
   2. Origins
   3. Absorption and filtering
   4. Selection of radiation
   5.  X-ray tube construction and geometry
   6. Safety