Volume 107, Number 5, September 2014
|Number of page(s)||6|
|Section||Condensed Matter: Structural, Mechanical and Thermal Properties|
|Published online||05 September 2014|
Anharmonic effects on thermodynamic properties of a graphene monolayer
1 Instituto de Física, Universidade Federal de Goiás - 74001-970, Goiânia, GO, Brazil
2 Departamento de Matemática e Física, Pontifícia Universidade Católica de Goiás - 74605-010, Goiânia, GO, Brazil
3 Instituto de Física de São Carlos, Universidade de São Paulo - 13560-970, São Carlos, SP, Brazil
4 Departement Fysica, Universiteit Antwerpen - Groenenborgerlaan 171, 2020 Antwerpen, Belgium
Received: 16 July 2014
Accepted: 20 August 2014
We extend the unsymmetrized self-consistent-field method (USF) for anharmonic crystals to layered non-Bravais crystals to investigate structural, dynamical and thermodynamic properties of a free-standing graphene monolayer. In this theory, the main anharmonicity of the crystal lattice has been included and the quantum corrections are taken into account in an ℏ-expansion for the one-particle density matrix. The obtained result for the thermal expansion coefficient (TEC) of graphene shows a strong temperature dependence and agrees with experimental results by Bao et al. (Nat. Nanotechnol., 4 (2009) 562). The obtained value of TEC at room temperature (300 K) is and it becomes positive for . We find that quantum effects are significant for . The interatomic distance, effective amplitudes of the graphene lattice vibrations, adiabatic and isothermal bulk moduli, isobaric and isochoric heat capacities are also calculated and their temperature dependences are determined.
PACS: 65.80.Ck – Thermal properties of graphene / 68.65.Pq – Graphene films / 65.40.De – Thermal expansion; thermomechanical effects
© EPLA, 2014
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.