Bond length can be determined between different elements in molecules by using the atomic radii of the atoms. Carbon bonds with itself to form two covalent network solids. Diamond 's C-C bond has a distance of Sqrt[3]a/4 ≈ 0.154 nm away from each carbon since a diamond ≈ 0.357 nm, while graphite 's C-C bond has a distance of a/Sqrt[3] ≈ 0.142 nm away from each carbon since a graphite ≈ 0.246 nm. Although both bonds are between the same pair of elements they can have different bond lengths.