The number of atoms (z) in a simple cubic unit cell is one.
A crystal lattice comprises several unit cells. In a unit cell, every constituent particle( atom, molecule or ion ) has a specific and fixed position called lattice site.
There are four types of cubic cell
- A Simple Cubic Unit Cell – There is only 1 atom in a simple cubic unit cell.
- Body centered Cubic Unit Cell- Total 2 atoms present in a body centred unit cell.
- Face centered Cubic Cell – Total atoms present in a face-centred unit cell is 4 atoms
- End centered cubic cell – Total atoms present in an end-centered cubic unit cell is 2 atoms
For a simple cubic unit cell, 8 atoms are located on 8 corners of the lattice. Each atom located on the corner contributes 1/8th of the original volume of the cell.
Therefore, 8 × 1/8 = 1 atom