The face-centered cubic lattice is also referred to as cubic close-packed.
In the diagram at the left a face-centred cubic arrangement is constructed from different close-packed layers represented by the different colours. Only one sphere of each blue close-packed layer is shown.
In the diagram at the left a face-centred cubic arrangement is constructed from different close-packed layers represented by the different colours. Only one sphere of each blue close-packed layer is shown.
- Note that the same line passes through the center of both blue spheres. Spheres in the blue close-packed layers are directly above one another in a cubic close-packed lattice.
- Note that the line passing through the center of the blue spheres passes between a triangle of gold spheres and between a triangle of green spheres.
Spheres in the green and gold close-packed layers are not directly above or below each other or the spheres in the blue close-packed layer. Thus the close-packed layers are arranged in an ABCA……. packing pattern with the first and fourth layers being equivalent
In contrast,the portion of the hexagonal close-packed lattice at the right shows that first and third close-packed layers are equivalent (directly above one another). Thus in this lattice the packing of close-packed layers is ABA….