Eur. Phys. J. D 52, 71-74 (2009)
https://doi.org/10.1140/epjd/e2008-00256-2

Comparison of Raman spectra and vibrational density of states between graphene nanoribbons with different edges

¹ NanoScience Center, Department of Physics, 40014 University of Jyväskylä, Jyväskylä, Finland
² NanoScience Center, Department of Chemistry, 40014 University of Jyväskylä, Jyväskylä, Finland

Corresponding author: ^a sami.malola@phys.jyu.fi

Received: 19 September 2008
Published online: 24 January 2009

Abstract

Vibrational properties of graphene nanoribbons are examined with density functional based tight-binding method and non-resonant bond polarization theory. We show that the recently discovered reconstructed zigzag edge can be identified from the emergence of high-energy vibrational mode due to strong triple bonds at the edges. This mode is visible also in the Raman spectrum. Total vibrational density of states of the reconstructed zigzag edge is observed to resemble the vibrational density of states of armchair, rather than zigzag, graphene nanoribbon. Edge-related vibrational states increase in energy which corroborates increased rigidity of the reconstructed zigzag edge.