Surface phonons of the hydrogen-terminated Si(111)(1×1) surface

By use of high-resolution electron-energy-loss spectroscopy, the dispersion of the Si-H stretching and bending vibrations and of substrate phonons was measured for the Si(111)-H(1×{}1) surface, which was prepared by wet chemistry. The results were compared to two different theoretical calculations based on the bond-charge model and a force-constant model. None of the two models achieves a satisfactory quantitative description of the surface dynamics.