We have measured the phonon dispersion relations of 4H-SiC by inelastic x-ray scattering (IXS) using monochromatized synchrotron radiation. The q-space directions Gamma-K-M, Gamma-M, and Gamma-A were mapped out. Lattice dynamical calculations that allowed the prediction of phonon eigenvectors, as well as their symmetries, also helped in choosing the best scattering geometries. The IXS phonon data are compared with those previously obtained from low temperature photoluminescence measurements and from laser Raman spectroscopy.
