Elastic properties of graphene flakes: boundary effects and lattice vibrations

Abstract

We present a calculation of the free energy, the surface free energy and the elastic constants ("Lam'e parameters" i.e, Poisson ratio, Young's modulus) of graphene flakes on the level of the density functional theory employing different standard functionals. We observe that the Lam'e parameters in small flakes can differ from the bulk values by 30% for hydrogenated zig-zag edges. The change results from the edge of the flake that compresses the interior. When including the vibrational zero point motion, we detect a decrease in the bending rigidity by ~26%. This correction is depending on the flake size, N, because the vibrational frequencies flow with growing N due to the release of the edge induced compression. We calculate Grueneisen parameters and find good agreement with previous authors.

11 pages, 12 figures

References in corpus (31)

• Electric Field Effect in Atomically Thin Carbon Films
• The electronic properties of graphene
• The Raman Fingerprint of Graphene
• Two Dimensional Atomic Crystals
• Energy Gaps in Graphene Nanoribbons
• The structure of suspended graphene sheets
• Half-Metallic Graphene Nanoribbons
• Unconventional quantum Hall effect and Berry's phase of 2pi in bilayer graphene
• Uniaxial Strain in Graphene by Raman Spectroscopy: G peak splitting, Gruneisen Parameters and Sample Orientation
• Atomic Structure of Graphene on SiO2
• Electronic States of Graphene Nanoribbons
• A tight-binding approach to uniaxial strain in graphene
• Ripple Texturing of Suspended Graphene Atomic Membranes
• Raman Spectroscopy of Graphene Edges
• Magnetism in graphene nano-islands
• Self-passivating edge reconstructions of graphene
• Phase Coherent Transport of Charges in Graphene Quantum Billiard
• Effects of Strain on Electronic Properties of Graphene
• Periodically rippled graphene: growth and spatially resolved electronic structure
• High-Resolution Scanning Tunneling Microscopy Imaging of Mesoscopic Graphene Sheets on an Insulating Surface
• Finite temperature lattice properties of graphene beyond the quasiharmonic approximation
• Nonlinear elasticity of monolayer graphene
• Energy gaps in etched graphene nanoribbons
• Subjecting a graphene monolayer to tension and compression
• Strain-induced pseudo-magnetic field for novel graphene electronics
• Shot Noise in Ballistic Graphene
• Strained graphene: tight-binding and density functional calculations
• Graphene under hydrostatic pressure
• First principles study of magnetism in nanographenes
• Edge Effects in Finite Elongated Graphene Nanoribbons
• First-principles study of graphene edge properties and flake shapes

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• Uniaxial strain-induced Kohn anomaly and electron-phonon coupling in acoustic phonons of graphene
• Vibrational properties of nanographene
• Designing Moire Patterns by Shearing