Interlayer repulsion and decoupling effects in stacked turbostratic graphene flakes

Abstract

We have explored the electronic properties of stacked graphene flakes with the help of the quantum chemistry methods. We found that the behavior of a bilayer system is governed by the strength of the repulsive interactions that arise between the layers as a result of the orthogonality of their $\pi$ orbitals. The decoupling effect, seen experimentally in AA stacked layers is a result of the repulsion being dominant over the orbital interactions and the observed layer misorientation of 2$^{\circ}-5^{\circ}$ is an attempt by the system to suppress that repulsion and stabilize itself. For misorientated graphene, in the regions of superposed lattices in the Moir\'e pattern, the repulsion between the layers induce lattice distortion in the form of a bump or, in rigid systems local interlayer decoupling.Comment: 4 pages, 3 figure