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Abstract: Scanning Tunnelling Microscopy, High Resolution Electron Energy Loss Spectroscopy and High Resolution X-Ray Photoelectron Spectroscopy have been used to study the adsorption of atomic hydrogen onto Si nanowires grown on Ag(110). We demonstrate that the hydrogen strongly interacts with the Si nanowires modifying their structural and electronic properties. Hydrogen atoms etch the Si nanowires and eventually lead to their complete removal from the Ag(110) surface. [Copyright &y& Elsevier]

Abstract: We have herein studied the adsorption of tin-phthalocyanine on the indium rich 4×2/c(8×2) reconstruction of the InSb(001) surface, using scanning tunneling microscopy, low-energy electron diffraction and high-resolution electron energy loss spectroscopy. The tin-phthalocyanine molecules form a stable monolayer with a characteristic long-range one-dimensional order, imposed by the twofold symmetry of the substrate surface reconstruction. High-resolution electron energy loss studies of both the vibrational and the electronic eigenmodes of the molecules show that phthalocyanines lie flat on the surface. In that, they behave the same way as lead phthalocyanines, which leads us to suggest that a common adsorption configuration may be adopted by non-planar phthalocyanines on the InSb(001)-4×2/c(8×2) surface. [Copyright &y& Elsevier]

Sub-monolayer and monolayer of lead phthalocyanine deposited on InSb(100) (4×2)/c(8×2) surface have been investigated by scanning tunneling microscopy and low energy electron diffraction. Molecules first adsorb on the indium rows of the (4×2)/c(8×2) structure in the [110] direction and diffuse at the surface in order to form two-dimensional islands. The molecule–substrate interaction stabilizes the PbPc molecules on the In rows. It weakens the interaction between molecules located in adjacent rows resulting in numerous gliding planes between the molecular chains, in the direction parallel to the rows. At monolayer completion, a long-range one-dimensional order is adopted by the molecules in the [110] direction. [Copyright &y& Elsevier]

Abstract: We modeled damaged-irradiated carbon plasma facing component PFCs by graphite surfaces with vacancies. We combined theoretical and experimental investigations with a view to building tools to make a better assignment of the observed defects from the scanning tunneling microscope (STM) images. The theoretical part of this work is based on periodic density functional theory calculations. The electronic structure is calculated and the density of state along with the electronic density near the Fermi level are plotted. STM images are further simulated and their features are interpreted. On the experimental side, we performed scanning tunneling microscopy (STM) imaging at low bias voltage in order to probe the electronic modifications of the graphite surface induced either by H+ (or D+) ion bombardment and/or atomic H (respectively D) adsorption. A connection between STM images and the reactivity of defective graphite surfaces towards H is also proposed. [Copyright &y& Elsevier]

We have investigated the effect of hydrogen interaction with silicene monolayer and multilayer films grown on Ag(111) by means of scanning tunneling microscopy, low energy diffraction and high-resolution electron energy loss spectroscopy. On monolayer silicene, we demonstrate that the recently reported hydrogenated γ-(3 × 3) is indeed observed, but is found often in coexistence with the usual “flower” pattern of the clean silicene-(3 × 3), also labeled α-(3 × 3). In the vibrational spectra, features related to Si H vibrational modes show shifts towards lower energies as compared to hydrogenated Si surfaces. This substantial bond softening is indicative of a partial charge filling of the bonding or anti-bonding orbitals of the Si H bonds as compared to Si(111) H. Indirectly, this is an evidence of the hybridization of monolayer silicene with the Ag(111) substrate. At multilayer coverage, the situation is clearly different. Indeed, hydrogen strongly perturbs the √3 × √3 reconstruction of the multilayer film, leading to its local dissolution and to the formation of protrusions due to clustering of atoms. The vibrational spectrum of the √3 × √3 silicene closely resembles that of a highly hydrogenated Si surfaces, with the simultaneous presence of Si H, Si H 2 and Si H 3 bonds. [ABSTRACT FROM AUTHOR]