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arXiv · 1208.0725

Pressure coefficients of Raman modes of carbon nanotubes resolved by chirality: Environmental effect on graphene sheet

A. J. Ghandour·I. F. Crowe·J. E. Proctor·Y. W. Sun·M. P. Halsall·I. Hernandez·A. Sapelkin·D. J. Dunstan
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Abstract

Studies of the mechanical properties of single-walled carbon nanotubes are hindered by the availability only of ensembles of tubes with a range of diameters. Tunable Raman excitation spectroscopy picks out identifiable tubes. Under high pressure, the radial breathing mode shows a strong environmental effect shown here to be largely independent of the nature of the environment . For the G-mode, the pressure coefficient varies with diameter consistent with the thick-wall tube model. However, results show an unexpectedly strong environmental effect on the pressure coefficients. Reappraisal of data for graphene and graphite gives the G-mode Grueuneisen parameter gamma = 1.34 and the shear deformation parameter beta = 1.34.

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A. J. Ghandour, I. F. Crowe, J. E. Proctor, Y. W. Sun, M. P. Halsall, I. Hernandez, A. Sapelkin, D. J. Dunstan. 2012-08-03. Pressure coefficients of Raman modes of carbon nanotubes resolved by chirality: Environmental effect on graphene sheet. https://doi.org/10.1103/physrevb.87.085416

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