1. Unit cell—a simple repeating pattern that
UNIT CELLS: use slide show mode
Unit cell—a simple repeating pattern that
contains all of the information about the structure

2. Are these unit cells?

3. Are these unit cells?

4. 2D Packing Examples
Answer the following questions for both packing diagrams.
Find the smallest unit that, if repeated, would give you the entire structure. This is the unit cell. Draw a box on the diagram representing the unit cell.
How many total atoms are inside the unit cell? Remember that only fractions of some atoms lie inside the box you drew.
Accurately draw boxes exactly 3 atoms wide. How many total atoms are in each? Which displays the greater packing density?
hole
hole

5. UNIT CELL POWERPOINT – Dr Jakubowski
SIMPLE CUBIC PACKING A A
TOP VIEW AA
unit cell: simple cubic
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Flash Anim | Jmol 1

6. BODY CENTERED CUBIC PACKING - ABAB
Unit cell: body centered cubic
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Flash Anim | Jmol 1

7. HEXAGONAL CLOSEST PACKING - ABAB
Side view
Top view
1200
Unit cell: hexagonal closest packing
External Web Links
Jmol

8. CUBIC CLOSEST PACKING B C A

9. A 6 A B C 7 8 3 4 5 C 1 2 B
Unit cell: face centered cubic 6 7 8 A 3 4 5
CUBIC CLOSEST PACKING 2 1
Dr J Jmol
External Web Links
Flash Anim | Jmol 1