DFT calculations reveal the most stable edge structures of graphene on Ni(111)
Garcia-Lekue A., Ollé M., Sanchez-Portal D., Palacios J. J., Mugarza A., Ceballos G., & Gambardella P. J., Phys. Chem. C, 111, 4072-4078 (2015)
Motivation of the modeling
Edges play a fundamental role in shaping the morphology and electronic properties of graphene nanostructures. Electron confinement due to edge boundaries gives rise to energy band gaps, localized states, spin-polarization, and spin-dependent electron scattering. Furthermore, graphene edges determine the preferred sites for the attachment of metal atoms and chemical functionalization, as well as oxygen etching and intercalation.
Achievements of the model
A detailed insight into the interplay of substrate interaction and edge morphology is achieved thanks to the combination of experiments and theory. The most stable edge structures of graphene on Ni(111) as well as the role of stacking-driven activation and suppression of edge reconstruction are revealed.
Density Functional Theory (DFT) calculations, as implemented in the SIESTA and ANT.G codes, confirm and complement Scanning Tunneling Microscopy (STM) results. In summary, the following points were addressed:
The following key issues were investigated:
- Investigation of the structure, stability, and epitaxial relationship between the graphene edges
and a metallic substrate
- Information on the edge stability and energetics
Juan Jose Palacios, part of the SIMUNE´s board of experts and developer of ANT.G is one of the authors of this work.