A grain boundary in highly-oriented pyrolytic material was investigated by means of scanning tunnelling microscopy. A periodic structure was observed along the boundary. Crystallographic models were constructed in order to explain the bonding between the two grains, and scanning tunnelling microscopy theoretical simulations were carried out. It was concluded that pentagon–heptagon chains probable existed at the boundary.

STM Study of a Grain Boundary in Graphite. P.Simonis, C.Goffaux, P.A.Thiry, L.P.Biro, P.Lambin, V.Meunier: Surface Science, 2002, 511[1-3], 319-22