By using ab initio molecular dynamics calculations, we show that even where the graphene lattice constant contracts, as previously reported for freestanding graphene below room temperature, the average carbon-carbon distance increases with temperature, in both free and supported graphene. This results in a larger corrugation at higher temperature, which can affect the interaction between graphene and the supporting substrate. For a weakly interacting system as graphene/Ir(111), we confirm the results using an experimental approach which gives direct access to interatomic distances.
Thermal Expansion of Supported and Freestanding Graphene: Lattice Constant versus Interatomic Distance / Pozzo, M; Alfe, D; Lacovig, P; Hofmann, P; Lizzit, S; Baraldi, A. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 106:13(2011). [10.1103/PhysRevLett.106.135501]
Thermal Expansion of Supported and Freestanding Graphene: Lattice Constant versus Interatomic Distance
Alfe D;
2011
Abstract
By using ab initio molecular dynamics calculations, we show that even where the graphene lattice constant contracts, as previously reported for freestanding graphene below room temperature, the average carbon-carbon distance increases with temperature, in both free and supported graphene. This results in a larger corrugation at higher temperature, which can affect the interaction between graphene and the supporting substrate. For a weakly interacting system as graphene/Ir(111), we confirm the results using an experimental approach which gives direct access to interatomic distances.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.