1. Graphite forms a two dimensional layer structure with C – C bonds within the layers.
2. There are relatively weak interactions between the layers.
3. In the layer structure, the carbon atoms are in a trigonal planar environment.
4. This is consistent with each carbon atom in sp2 hybridisation.
5. Interactions between the sp2 orbitals (overlaps) lead to the formation of C – C bonds.
6. Each carbon atom is with one unhybridised ‘p’ orbital.
7. The unhybridised ‘p’ orbitals interact to form a π system that is delocalised over the whole layer.
8. The interactions known as London dispersion forces between the layers which are separated by a distance of 3.35 A° are weakened by the presence of water molecules so that it is easy to cleave graphite.
9. For this reason graphite is used as lubricant and as the lead in pencils.
