1. PY3090 Preparation of Materials Lecture 2 Colm Stephens School of Physics

2. (Primitive) Cubic e.g. Mn

3. Body Centred Cubic (BCC) e.g.  -Fe, V, Cr, Mo, W

4. Face Centred Cubic (FCC) e.g.  -Fe, Al, Ni, Cu, Ag, Pt, Au

5. Hexagonal Close Packed (HCP) e.g. Be, Mg,  -Ti, Zn, Zr

6. HCP Unit cell – plan view 1 st layer r at

7. HCP Unit cell – plan view 2 nd layer r at

8. HCP Unit cell – side view 2 layers r at C/2

9. HCP reduced sphere view h

10. Close Packing FCC vs. HCP

11. Caesium chlorideCubic (Primitive) cubic

12. Sodium chlorideFCC

13. CristoboliteFCC e.g. SiO 2

14. Diamond cubic (FCC) e.g. Si, Ge, grey-Sn

15. Zinc blende (FCC) e.g. GaAs, AlP, InSb ( III-V SCs) ZnS, CdS, HgTe ( II-VI SCs)

16. Carbon polymorphism Graphite

17. Carbon polymorphism Buckminster Fullerene C60 Carbon nanotube

18. Imperfections Point defects

19. Lattice strains Tensile Compressive

20. Notice lattice strains Point defects

21. Edge Dislocation

22. Burgers Vector 5 4 4 4 1

23. Screw Dislocation

24. Mixed Dislocation