Face-Centred Cubic
A cubic arrangement with particles at the eight corners and at the centre of each of the six faces.
Formula / equation
4 atoms per cell, 74% packing
Unit
Dimensionless
In depth
Each face atom is shared between two cells, giving four atoms per cell, a coordination number of twelve and the maximum possible packing efficiency of 74%. Also called cubic close packing, it gives metals many slip planes and hence excellent ductility.
Examples in the real world
Copper, aluminium, silver, gold and nickel; the chloride sublattice of rock salt is also face-centred cubic.