CARBON: graphite structure

(above) graphite #4 (graphite structure).

Graphite: consists of carbon atoms arrayed in a hexagonal pattern in large parallel sheets. These individual sheets (known as graphene) are shown encased in coloured blocks for clarity. The bottom layer has been extended out to the right to clearly show the hexagonal arrangement of the carbon atoms. Alternate sheets are out of phase with each other so that a carbon atom in one sheet lies in line with the hole at the centre of the hexagonal rings above and below. This is illustrated in two ways:

1. A hexagonal blue column passes through all four layers. At the top (maroon) layer it has a carbon atom at its centre. In the next (orange) layer, the column is centred on the hole in the middle of a hexagonal carbon ring.

2. The maroon and orange boxes that enclose the four layers are seen to be staggered. The ones of each colour are directly in line with each other (i.e orange is directly in line with orange).

The sheets can slide across each other (helped by contaminants) giving graphite its lubricating and writing properties. Electrons can travel along the strata making graphite an electrical conductor in a direction parallel with the plates.

The carbon atoms are shown as silvery or pearlescent spheres drawn at their covalent radius (i.e. just touching).

Image on this page is 500 pixels across, the original is 4096 pixels across.