Article

Doable resonant Raman scattering in graphite

Institut fur Festkorperphysik, Technische Universitat Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany.
Physical Review Letters (Impact Factor: 7.73). 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 cm(-1)/eV) agrees well with the experimental value.

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