Importance of edge atoms

The issues of grain boundaries and surface (re)construction in solids, either crystalline or amorphous, are a very important part of materials science and engineering. In sp2 hybridized carbon materials, the atoms at graphene edges have been of interest for many decades and in several different contexts; more recently, the interest in graphene nanoribbon (GNRs) materials has brought these issues into sharp focus again. As the crystallite dimensions of any carbon material decrease, the importance of ‘external’ edge atoms increases. This applies particularly to ‘nanocarbons’ where either the size or the structure is controlled at the nanometer scale [1].