Type: Article
Publication Date: 2007-07-30
Citations: 425
DOI: https://doi.org/10.1103/physrevb.76.035439
We present the full in-plane phonon dispersion of graphite obtained from inelastic x-ray scattering, including the optical and acoustic branches, as well as the midfrequency range between the $K$ and $M$ points in the Brillouin zone, where the experimental data have been unavailable so far. The existence of a Kohn anomaly at the $K$ point is further supported. We fit a fifth-nearest neighbor force-constant model to the experimental data, making improved force-constant calculations of the phonon dispersion in both graphite and carbon nanotubes available.