Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Cubic closest packing (CCP) is a type of crystal lattice structure where spheres are packed in the most efficient manner, resulting in a repeating ABCABC pattern. This arrangement maximizes space utilization and has a coordination number of 12.
5 Must Know Facts For Your Next Test
CCP is also known as face-centered cubic (FCC) packing.
The unit cell of CCP contains four atoms: one at each corner and one at the center of each face of the cube.
The coordination number in CCP is 12, meaning each atom is surrounded by 12 nearest neighbors.
CCP structures have a packing efficiency of approximately 74%.
Examples of elements that crystallize in CCP include aluminum, copper, and gold.
The number of nearest neighbor atoms or ions surrounding an atom or ion in a crystal lattice.
Face-Centered Cubic (FCC): A type of crystal lattice structure where atoms are located at each corner and at the center of each face of the cube.
Hexagonal Closest Packing (HCP): A type of crystal lattice structure with a repeating ABAB pattern, resulting in each atom having a coordination number of 12.