RT Journal Article
T1 Anharmonicity effects in the frictionlike mode of graphite
A1 Menéndez, Cesar
A1 Lobato Fernández, Álvaro
A1 Abbasi-Pérez, David
A1 Fernández-Núñez, José
A1 Recio, Jose Manuel
A1 García Baonza, Valentín
AB Graphite is a prototypical solid lubricant demanding a thorough understanding of its low-friction behavior. The 𝐸2⁢𝑔(1) Raman active vibrational mode of graphite is associated with the rigid-layer relative movement of its graphene sheets. Thus, this mode can provide a good means of exploring the low resistance of graphene layers to slip with respect to each other. To take advantage of this fact, the anharmonicity of the 𝐸2⁢𝑔(1) mode has to be carefully characterized and evaluated since the atomic arrangement of carbon atoms in the ambient condition ABA stacking of graphite evidences potential asymmetry. The calculated one-dimensional energetic profile of the 𝐸2⁢𝑔(1) mode reveals this local anisotropy around the energy minima and can be microscopically interpreted in terms of electron density interactions. Morse-type potentials accurately fit the energetic profiles at different interlayer separations, and provide simple analytical expressions for evaluating harmonic and anharmonic contributions to the Γ-point 𝐸2⁢𝑔(1) frequency 𝜔𝐸2⁢𝑔⁡(1) under a perturbative algebraic treatment. We quantify how the anharmonic contribution increases with the available energy (𝐸) at zero pressure, and how this contribution decreases as hydrostatic pressure (𝑝) or uniaxial stress is applied for a given available energy. The calculated 𝜔𝐸2⁢𝑔⁡(1)−𝑝 and 𝜔𝐸2⁢𝑔⁡(1)−𝐸 trends indicate an increasing (decreasing) of frictional forces in graphite with pressure (temperature). Our conclusions are supported by the good agreement of the calculated frequencies with existing Raman experiments under hydrostatic pressure conditions.
PB American Physical Society
SN 2469-9950
YR 2016
FD 2016
LK https://hdl.handle.net/20.500.14352/92329
UL https://hdl.handle.net/20.500.14352/92329
LA eng
NO Menéndez, C.; Lobato, A.; Abbasi-Pérez, D.; Fernández-Núñez, J.; Baonza, V. G.; Recio, J. M. Anharmonicity effects in the frictionlike mode of graphite. Phys. Rev. B 2016, 93, 144112 DOI:10.1103/PhysRevB.93.144112.
NO Principado de Asturias
NO Ministerio de Economía y Competitividad (España)
NO European Commission
DS Docta Complutense
RD 6 abr 2025