Zero Misorientation Interfaces In Graphene

This article presents the results on the modeling of straight-line interfaces that induce no misorientation of adjacent regions in graphene: zero misorientation interfaces (ZMIs). The interfaces in the hexagonal graphene lattice are represented as ensembles of disclinated carbon rings with broken rotational symmetry of the sixth order. The basic elements of such ensembles are structural units - complexes of disclinated rings with zero disclination charge. Using molecular dynamics simulation, the energies and atomic densities for ZMIs are found. Calculations demonstrate that atomic densities in ZMIs are lower than the atomic density in defect-free graphene. No direct correlation has been revealed between the atomic density and the interface energy. It is assumed, that the elastic field caused by ZMI defect structure contributes significantly to the energy of interface. Low-energy ZMIs possess linear energies not exceeding similar to 0.6-0.8 eV/angstrom, that is comparable to the energies of the grain boundaries, i. e. boundaries with misorientation, in graphene. Based on a mesoscopic approach operating with disclination schemes, in which defective carbon rings are replaced by disclinations, strain maps are plotted, and energies are found for two selected low-energy ZMIs. It is demonstrated that, at the distance of ZMI half-period from interface line, strains decrease to values of similar to 0.05. The energies of low-energy ZMIs calculated within the framework of two approaches: atomistic and mesoscopic, although differ numerically, coincide by the order of magnitude.