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Graphing and Grafting Graphene: Classifying Finite Topological Defects



Eric J. Cockayne


The structure of finite-area topological defects in graphene is described in terms of both the direct honeycomb lattice and its dual triangular lattice. Such defects are equivalent to cutting out a patch of graphene and replacing it with a different patch with the same number of dangling bonds. An important subset of these defects, bound by a closed loop of alternating 5- and 7-membered carbon rings, explains most finite-area topological defects that have been experimentally observed. Previously unidentified defects seen in scanning tunneling microscope (STM) images of graphene grown on SiC are identified as isolated divacancies or divacancy clusters.
Physical Review B


graphene, defects, topological defects, STM images, simulations


Cockayne, E. (2012), Graphing and Grafting Graphene: Classifying Finite Topological Defects, Physical Review B, [online], (Accessed April 21, 2024)
Created March 8, 2012, Updated October 17, 2022