INITIAL ROLL GUIDED STRUCTURAL TRANSITION OF GRAPHENE.

Molecular dynamics simulations have been performed to study the initial roll guided structural transition of graphene. The flat graphene is thermodynamic metastable and small disturbance can strike its balance and lead to fold. An initial roll at one end causes the graphene layer to transform into double-fold, multi-fold and scroll spontaneously, depending on the size of the initial roll. This unique phenomenon results from the combined action of the van der Waals interaction and the π-π stacking effect. The potential energy of the final structures decreases with the increase of compact level. This study provides crucial simulation input to help guide to designing the required graphene-based nanostructures. The flat graphene is thermodynamic metastable and an initial roll at one end can cause the graphene layer to transform into double-fold, multi-fold and scroll spontaneously, depending on the size of the initial roll. The suggested mechanism is that the vdW force among graphene layers induced by the initial roll provides sufficient attractive force to overcome the energy barrier, the π-π stacking effect between graphene layers cause the structure of graphene to transform spontaneously and stabilizes two parallel graphene walls to achieve the lowest energy AB stacking. [ABSTRACT FROM AUTHOR]