Article

# Double Resonant Raman Scattering in Graphite

Institut fur Festkorperphysik, Technische Universitat Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany.
(Impact Factor: 7.51). 01/2001; 85(24):5214-7. DOI: 10.1103/PhysRevLett.85.5214
Source: PubMed

ABSTRACT

We find that the electronic dispersion in graphite gives rise to double resonant Raman scattering for excitation energies up to 5 eV. As we show, the curious excitation-energy dependence of the graphite $D$ mode is due to this double resonant process resolving a long-standing problem in the literature and invalidating recent attempts to explain this phenomenon. Our calculation for the $D$-mode frequency shift ( $60{\mathrm{cm}}^{\ensuremath{-}1}/\mathrm{eV}$) agrees well with the experimental value.

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• ", two phonon double resonance Raman scattering process) as well as D band (introduction of defects) [29] [30] "
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• "I D /I G ratio was used to evaluate the average size of sp 2 domain and the degree of disorder and in present case the same is 0.14 which indicates high order and low degree of structural defects as a result of efficient deoxygenation of carboxyl , epoxy and other oxygen functional groups. The position, shape and full width half maximum (FWHM) of the second-order 2D band are sensitive to the number of layers in grapheme nanoplatelets (Ni et al. 2007; Ferrari and Robertson 2000; Ni et al. 2008), which may be triggered by double-resonant effect, in other words, may be caused by changes in electronic and vibrational properties (Thomson and Reich 2000) XPS scan was adopted to confirm remnant amount of oxygen functional groups that may impair the conductive network and electrochemically active surfaces for supercapacitor applications. The survey scan plotted in Fig. 8a shows C 1 s peak at about 284.78 eV and weak O 1 s peak at about 533.3 eV, which indicates lower oxygen content and the same has been confirmed by Fig. 8b and c. "
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02/2015; DOI:10.1007/s13204-015-0415-9
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• "The major Raman features of graphene and graphite are G band and 2D band (\$2675 cm À1 ). 2D band originates from a two phonon double resonance in Raman scattering process [25]. 2D band is also denoted as G 0 . "
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