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Interface between oxides and metals appears in a large number of technological fields and has thus been, so far, the focus of scientific investigations in physics, chemistry, and materials science. Among those research fields, oxide/metal interfaces play a relevant role also in magnetism and spintronics applications, where the metallic counterpart is typically a ferromagnet. This article briefly summarizes such a scientific context and provides some concepts and examples related to the particular case of layered magnetic structures. In such systems, ultrathin oxide films can be used, for instance, as tunneling barrier in so-called magnetic tunnel junctions and, in case of oxides that show a long-range antiferromagnetic order, as active layers in exchange bias systems. In such cases, in fact, thin and ultrathin oxides are in proximity to ferromagnetic metals, and the effects of this proximity, in particular those related to the chemistry at the interface, directly influence the magnetic properties of the system. A thorough understanding of these issues is of great importance in the long-term perspective of tailoring the magnetic effects, thus opening the possibility of designing novel technological applications.

We study the effect of electron and phonon degrees of freedom on the relaxation dynamics of adsorption processes in gas-surface systems by using ab initio molecular dynamics that incorporates an electronic friction force (AIMDEF). As representative cases we have chosen three systems with different adsorption energies and adsorbate-to-surface atom mass ratios: H on Pd(1 0 0), N on Ag(1 1 1), and on Fe(1 1 0). We show, through inspection of the total energies and trajectories of the hot adsorbates on the surface, that electron–hole (e–h) pair excitations dominate relaxation of the light gas species, while the phonon channel is dominant for the heavy species. In the latter case e–h pairs become more important at the final thermalization stages., This work has been supported by the Basque Departamento de Educación, Universidades e Investigación, the University of the Basque Country UPV/EHU (Grant No. IT-756-13) and the Spanish Ministerio de Economía y Competitividad (Grant No. FIS2013-48286-C2-2-P).

Inorganically driven fouling of metal heat-transfer surfaces employed in crude oil refining operations is not well understood. The object of this study is twofold: First, we systematically elucidate the time-dependent mechanism of the interrelated carbonaceous and sulfidic build up that occurs at high temperatures on a metal surface (540 °C metal temperature, 250 °C oil bath temperature). Second, we demonstrate that additions of 0.5, 1.3 and 5.7 vol% thiophene (C 4 H 4 S) cause a 2×, 10×, and 20× reduction in the fouling factor after a 1400 min exposure. Analytical techniques including TEM, SEM–EDX, FIB, Auger electron spectroscopy and XRD were employed to detail the fouling phenomenology for a heated stainless steel wire immersed in atmospheric bottoms fraction crude oil, exposed for 1–1400 min. A key microstructural observation is the transformation of the wire’s as-received near-surface textured austenitic grain structure into a micron scale (e.g. ∼10 μm at 1400 min) highly porous inner-sulfide/chromium oxide bilayer composite. Additionally, we observe significant localized sulfidic attack into the bulk of the metal. During testing, an iron sulfide (pyrrhotite Fe (1 − x ) S) corrosion product forms almost instantaneously at the metal surface, followed by coke formation around its periphery at longer times. This temporal sequence, combined with the observation that the thicker regions of the foulant are clearly associated with detached plumes of the sulfide, leads us to argue that the sulfide is essential for promoting organic fouling. This is brought about by the sulfide’s action as a potent dehydrogenation catalyst that drives the transformation of pitch to coke. We hypothesize that the tremendous fouling inhibition effect of the thiophene originates from its adsorption onto the sulfide surfaces, thereby blocking the dehydrogenation reactions.

Adhesion of the bacterial strain Staphylococcus epidermidis 3399 to titanium-oxy-nitride (TiNOX (R)) substrata with different specific resistivities was studied in a parallel plate flow chamber, while simultaneously measuring the electric potential of the substrata. During adhesion, bacteria either donated or accepted electrons to the substrata depending on the specific resistivity of the substratum and bacteria that had donated electrons to the substratum adhered more strongly than bacteria that had accepted electrons from the substratum. These results demonstrate that electron transfer plays a role in bacterial adhesion to conducting surfaces, which has hitherto been neglected. (C) 2000 Elsevier Science B.V. All rights reserved.

We present calculation results for electron–phonon (e–ph) coupling in one monolayer (ML) of Na on the Cu(1 1 1) surface. We show that the e–p coupling parameter λ decreases compared to that for clean Cu(1 1 1) due to the significant decrease of the Na vertical vibrational mode contribution to the Eliashberg function in the 1 ML Na/Cu(1 1 1) system. The corresponding phonon induced lifetime broadening Γe–ph of a quantum-well state at low temperature decreases by 30% compared to that on clean Cu(1 1 1)., Partial support by the Basque Departamento de Educación, Universidades e Investigación, the University of the Basque Country UPV/EHU (Grant No. 9/UPV 00206.215-13639/2001), the Spanish MEC (Grant No. FIS2004-06490-C03-00), the Ministry of Science of Russia (Grant No. 40.012.1.1.1153) and NATO science programme (Grant PST. CLG. 980395) is acknowledged.

We report an ab initio study of electron–phonon interactions on the Be(0 0 0 1) surface. The calculations based on density-functional theory were carried out using a linear response approach in the plane-wave pseudopotential representation. The phonon-induced contribution to excited hole (electron) lifetime broadening is calculated for the zone center surface state. The obtained results show a rather strong momentum dependence., This work was supported by the NATO science programme (Grant PST. CLG. 980395), the Basque Country Government, and the European FP6 Network of Excellence (FP6-NoE NANOQUANTA (500198-2)).