1 / 29

Crystal structure determination and space groups

H. K. D. H. Bhadeshia. Crystal structure determination and space groups. 32 point groups. 14 Bravais Lattices. 14 Bravais lattices. add centres. 230 space groups. macroscopic symmetry. microscopic symmetry. 32 point groups. space groups locate atoms within a cell:

freira
Télécharger la présentation

Crystal structure determination and space groups

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  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.

More Related