Surface phonons ofC(001)(2×1)−H

Abstract

Surface phonons of the hydrogen-covered diamond surface $\mathrm{C}\mathrm{}\left(001\right)(2\mathrm{}\times 1)-\mathrm{H}$ have been studied by electron energy loss spectroscopy (EELS) combined with semiempirical total-energy calculations. EELS resolves several vibrational features in the energy region of the bulk phonon bands in addition to C-H stretch modes. From calculated depth-resolved spectral densities, the vibrational features are found to originate not only from the adsorbed hydrogen and the carbon surface dimer atoms but also from deeper layers of the diamond crystal. On the other hand, a nearly localized character of the vibrations along the surface is found from the measurements of the energy dispersions.