1. Crystalline Solids BLB 12 th Chapter 12 Sections 1-3, 5

2. Types of Crystalline Solidsp. 464

4. Macroscopic structure depends upon microscopic structure.

5. Fluorite (CaF 2 )Amethyst (SiO 2 ) – quartz + Fe & Mn Pyrite (FeS 2, fool’s gold)

6. Crystalline – atoms, ions, or molecules arranged orderly –Ionic compounds, diamond, sugar, ice Amorphous – “without form”; lack the order of solids –Glass, plastic, wax, ceramics

7. Crystal Terms Crystal – Crytal Lattice – Unit cell – Cell dimensions – a, b, c, α, β, γ corner edge face

8. Crystalline lattice in two dimensions

10. Crystalline lattice in three dimensions

11. Filling the unit cell

12. Types of Unit Cells

13. Atoms and ions are represented by spheres. The spheres stack in different patterns three- dimensionally. The close packing of spheres maximizes intermolecular force. The patterns of stacking result in different types of unit cells and lattices. Packing in Crystals

14. p. 468

15. Types of cubic unit cells

17. Body-centered cubic unit cell of C 60

18. Types of cubic unit cells Three items to determine for each type: 1.Number of atoms per unit cell 2.Number of nearest neighbors for each atom 3.Relationship between sphere radius and the cell edge length, d o ?

21. Primitive (simple) Cubic _______ atoms per unit cell _______ nearest neighbors

22. Body-centered Cubic _______ atoms per unit cell _______ nearest neighbors

23. Face-centered Cubic (result of close packing) _______ atoms per unit cell _______ nearest neighbors

24. Close packing

26. Close Packing Hexagonal close-packed (hcp) ABAB layers Cubic close-packed (ccp) ABCABC layers

27. Close packing unit cell types

28. What about the space left over?