| AVS 58th Annual International Symposium and Exhibition | |
| Graphene and Related Materials Focus Topic | Wednesday Sessions |
| Session GR+MN-WeM |
| Session: | Graphene: Mechanical and Thermal Properties, Graphene MEMS and NEMS |
| Presenter: | Brad Steele, University of South Florida |
| Authors: | B. Steele, University of South Florida V.V. Zhakhovsky, University of South Florida R. Perriot, University of South Florida I.I. Oleynik, University of South Florida |
| Correspondent: | Click to Email |
It has long been predicted by Peierls, Landau, and Mermin that infinite two-dimensional solids are unstable and should melt at any finite temperature. The stability of graphene, a two-dimensional layer of carbon atoms, is thus explained by the presence of an additional degree of freedom that allows it to buckle in the third direction normal to the 2-D perfect plane. We performed large-scale molecular dynamics (MD) simulations of graphene melting in order to provide a fundamental insight into the stability of graphene, as well as to investigate the nature of the defects naturally created by thermal excitations at high temperatures. We will discuss the types of defects appearing before melting, the atomic-scale mechanisms of melting, and the nature of the resulting carbon melt. In addition, the graphene melting in 3D space versus 2D-constrained melting is also discussed. The importance of a proper description of chemical bonding in graphene at high temperatures is illustrated using different interatomic potentials: the reactive bond order (REBO) potential and the newly developed screened environment dependent SED-REBO. Comparisons with other recent simulations of graphene melting (including those using the LCBOPII potential for carbon) are also presented.