Best Answer: The coordination number of a lattice tells you how many other atoms are connected to each atom. Think about a cubic unit cell: it has eight vertices. If we had an atom in the middle, it would be connected to all eight of those atoms, and thus have a coordination number of eight. read more
the coordination number of a given atom in the interior of a crystal lattice is the number of atoms touching the given atom. a body-centered cubic (BCC) crystal in which each interior iron atom occupies the centre of a cube formed by eight neighbouring iron atoms. The bulk coordination number for this structure is therefore 8. read more