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Crystal Structure Determination & Space Groups: Solving Unknown Structures with Macroscopic & Microscopic Symmetry

Learn how crystallography identifies unknown structures by locating atoms in a unit cell utilizing 32 point groups and 230 space groups. Explore 14 Bravais lattices and the relationships between symmetry elements within crystals.

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Crystal Structure Determination & Space Groups: Solving Unknown Structures with Macroscopic & Microscopic Symmetry

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  1. H. K. D. H. Bhadeshia Crystal structure determination and space groups

  2. 32 point groups

  3. 14Bravais Lattices

  4. 14 Bravais lattices add centres 230 space groups macroscopic symmetry microscopic symmetry 32 point groups space groups locate atoms within a cell: help solve unknown structure 7 crystal systems

  5. a axial glide

  6. Cuprite

  7. P 42

  8. y x P n diagonal glide parallel to (100)

  9. Centre of symmetry at height 3/4

  10. centre of symmetry

  11. mirror triad

  12. Caesium chloride determine unit cell by diffraction to be cubic-P how many atoms per unit cell? space group of CsCl? location of atoms? 36 space groups possible

  13. 1/4 1/4 1/4 1/4 1/4 3/4 3/4 3/4 1/4 3/4 Lattice: face-centred cubic Motif: C at 0,0,0 C at 1/4,1/4,1/4

  14. 3/4 1/4 1/4 3/4 Lattice: face-centred cubic Motif: Zn at 0,0,0 S at 1/4,1/4,1/4

  15. tetragonal

  16. space group diagram

  17. Z. anorg. allg. Chem., 552: 69–80. doi: 10.1002/zaac.19875520907

  18. Assignment Draw an accurate stereographic projection of a cubic crystal, and mark on it the poles of the form 100, 110 and 111. Without measuring angles, but using vector addition, mark accurately, poles of the form 112 Ensure that the method you use is clear.

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