ABSTRACT

There are now three well established crystalline phases of carbon; diamond, graphite and crystalline C6o molecules. These phases are distinguished by their bonding; sp3 in diamond, sp2 in graphite, and a combination of intra-molecular sp2 and inter-molecular van der Waals bonding in C6o* There is also a large variety of non-crystalline carbons due to the different forms of bonding and different degrees of disorder, as summarised in Table 1.