Structural study of clean and oxygen-covered Fe(110) by surface extended energy-loss fine-structure technique

Clean and oxygen-covered Fe(110) has been studied by surface extended energy-loss finestructure technique. From the oscillations above the Fe M₂₃ edge the radial distribution functions, for 6 and 100 langmuir of oxygen at 300 K, are obtained. A larger distance between iron atoms is observed for 6 L of oxygen exposure and the O-Fe distance is found. At 100 L coverage the iron surface seems to reconstruct to the hexagonal structure of the FeO(111).     

Density of states of the clean Mo (110) surface

The electronic structure of the (110) surface of Mo is calculated using transfer matrix method. The Hamiltonian is of tight-binding type with a basis of nine orbitals per atom. Spectral densities of states for special points of the 2-D Brillouin zone are presented on the surface and in the three consecutive layers. The band structure in the σ direction and the local density of states are also calculated. The results are compared with the few experimental data available in the literature.     

The preparation and surface structure of clean V(110)

The first quantitative determination of the surface structure of a group VB metal is reported. A procedure is described for the preparation of a clean, well-ordered surface of V(110), free from the major bulk impurity, oxygen. The clean surface exhibits the two-dimensional periodicity of the corresponding bulk plane. Experimental LEED intensity measurements are compared to the results of multiple-scattering model calculations, with very good agreement being obtained for a value of the first interlayer spacing d, close to the bulk value. Minimization of the r factor for the comparison of experimental and calculated intensity spectra leads to a value of $\text{d = 2.12 ± 0.02}\text{A}\text{?}$, compared to the bulk value of 2.14 Å.     

Photoinduced structural instability of the InP (110)-(1x1) surface

A scanning tunneling microscopy study reveals the removal of P and In atoms at intrinsic surface sites of InP (110)-(1x1) through an electronic mechanism under ns-laser excitation. Femtosecond nonresonant ionization spectroscopy detects desorption of P and In atoms associated directly with the bond rupture, and shows their translational energies characteristic of electronic bong breaking. The rate of P-atom removal is 4 times higher than that of In-atom removal, revealing a prominent species-dependent effect of structural instability under electronic excitation on semiconductor surfaces.     

Electron energy loss spectra of a Pd(110) clean surface

Electron energy loss spectra of a Pd(110) clean surface have been measured at primary energies of 40–100 eV. The observed peaks are at the loss energies of ∼ 3, 4.3, 7.5, 11.5, 16, 21.3, 26.5 and 33.8 eV. The 7.5, 26.5, and 33.8 eV peaks are attributed mainly to the bulk plasmon excitations associated with 5s electrons, coupled 5s and a limited number of 4d electrons, and total (4d+5s) electrons, respectively. The rest of the peaks are ascribed mainly to one-electron excitations.