**Crystalline solids** represent structures with well-organized patterns and shapes.

Concept #1: Crystalline Solids

Unlike **crystalline solids**, **amorphous solids** represent structures that lack an organized patterns or shapes.

When examining the particles within a crystal you may observe them tightly packed in an organized pattern. The smallest portion of which is termed the **unit cell**.

There are 7 crystal systems and 14 types of unit cells that naturally occur. The **simple** **cubic unit cell **represents one of the simplest types.

Concept #2: Simple Cubic Unit Cell

The **Simple Cubic Unit Cell** is composed of a cube with an atom at each corner. In the **Lattice Diagram** each of the unit cells are combined to form a crystal lattice. In the **Space Filling Unit Cell Diagram** we are shown that the unit cell uses only 1/8 of each of the 8 corner atoms.

The **body-centered cubic unit cell **is composed of a cube with one atom at each of its corners and one atom at the center of the cube.

Concept #3: Body Centered Cubic Unit Cell

The **face-centered cubic unit cell** is composed of a cube with one atom at each of its corners and one atom in the center of each cube face.

Concept #4: Face Centered Cubic Unit Cell

Example #1: Unit Cell Calculations 1

Example #2: Unit Cell Calculations 1

Example #3: Unit Cell Calculations 1

Example #4: Unit Cell Calculations

Example #5: Unit Cell Calculations 2

Example #6: Unit Cell Calculations 2

Example #7: Unit Cell Calculations 2

Example #8: Unit Cell Calculations 3

Example #9: Unit Cell Calculations 3

Example #10: Unit Cell Calculations 3