A scanning tunneling microscopy (STM) study, combined with density functional theory (DFT) calculations and thermal desorption spectroscopy (TDS) data, on the growth and structure of Zn on a Pd(111) surface is presented. The STM results demonstrate that PdZn(111) surface alloy bilayer islands with a p(2 × 1) structure already form during the room temperature deposition of submonolayer amounts of Zn on Pd(111). DFT calculations predict that the PdZn bilayers are energetically more stable than single PdZn layers and establish their structural parameters. The TDS data show that Zn desorbs below 600 K in a multiple-peak desorption structure with fractional order desorption kinetics of the individual components, which is due to multilayer Zn desorption. The experimentally derived adsorption energies of the low temperature desorption peaks are reproduced in the DFT calculations. At temperatures above 750 K, Zn desorbs from the PdZn alloy, and the desorption kinetics is a mixture of a first-order and a diffusion-limited desorption process.

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We have studied the topological insulator Bi2Te3(111) by means of helium atom scattering. The average electron-phonon coupling λ of Bi2Te3(111) is determined by adapting a recently developed quantum-theoretical derivation of the helium scattering probabilities to the case of degenerate semiconductors. Based on the Debye-Waller attenuation of the elastic diffraction peaks of Bi2Te3 (111), measured at surface temperatures between 110 K and 355 K, we find λ to be in the range of 0.04 − 0.11. This method allows to extract a correctly averaged λ and to address the discrepancy between previous studies. The relatively modest value of λ is not surprising even though some individual phonons may provide a larger electron-phonon interaction. Furthermore, the surface Debye temperature of Bi2Te3(111) is determined as ΘD = (81 ± 6) K. The electronic surface corrugation was analysed based on close-coupling calculations. By using a corrugated Morse potential a peak-to-peak corrugation of 9% of the lattice constant is obtained.

Helium atom scattering (HAS) was used to study the antimony Sb(111) surface beyond the hard-wall model. HAS angular distributions and drift spectra show a number of selective adsorption resonance features, which correspond to five bound-state energies for He atoms trapped in the surface-averaged He-Sb(111) potential. As their best representation, a 9-3 potential with a depth of 4.4 ± 0.1 meV was determined. Furthermore, the charge density corrugation of the surface was analyzed using close-coupling calculations. By using a hybrid potential, consisting of a corrugated Morse potential (short range) and a 9-3 potential (long range), a peak-to-peak corrugation of 17% was obtained. The kinematic focusing effects that occurred were in good agreement with surface phonon dispersion curves from already published density functional perturbation theory calculations.