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Atomistic modeling of bimetallic Fe-Pt nanoparticles is performed using the BFS method for alloys. A simple approach is introduced to analyze segregation to the surface and bulk ordering patterns as a function of particle size and composition. [ABSTRACT FROM AUTHOR]

The formation and stability of Ni and V nanowires on a stepped Rh(553) substrate is investigated using the BFS method for alloys via an atom-by-atom description of the formation process. In agreement with experiment, Ni is found to form one-dimensional wires attached to the surface steps, while V does not. However, a detailed analysis of the energetics reveals that there the apparent differences leave room for the possibility of alloying in the case of Ni and the formation of structures along the step in the case of V. [ABSTRACT FROM AUTHOR]

Atomistic simulations of low coverage Sn growth on Au(111) using the Bozzolo-Ferrante-Smith (BFS) method for alloys are presented. Simulated annealing and atom-by-atom analysis of the energetics explains the close competition between the experimentally observed surface alloying and layer-by-layer growth. [ABSTRACT FROM AUTHOR]

Abstract: An algorithm for the calculation of temperature dependent bulk properties of multicomponent systems is introduced and illustrated with the calculation of the coefficient of thermal expansion, equilibrium volume, energy of formation and compressibility of Ni–Ti–Nb shape memory alloys. [Copyright &y& Elsevier]

Abstract: Adsorption probability measurements (molecular beam scattering) have been conducted to examine the adsorption dynamics (i.e. the gas-surface energy transfer processes) of CO2 adsorption on the Zn-on-Cu(110) bimetallic system. The results indicate surface alloy formation, which is in agreement with prior studies. Depositing Zn at 300K on Cu(110), above the condensation temperature of CO2, leads to a “blocking” of CO2 adsorption sites by Zn which is incorporated in the Cu(110) surface. This apparent site blocking effect indicates a lowering of the CO2 binding energy on the alloyed surface as compared with the clean Cu(110) support. The Zn coverage has been calibrated by Auger electron spectroscopy and thermal desorption spectroscopy. [Copyright &y& Elsevier]

Abstract: Molecular beam scattering measurements have been conducted to examine the adsorption dynamics of CO2 on Cu(110). The initial adsorption probability, S 0, decreases exponentially from 0.43±0.03 to a value close to the detection limit (∼0.03) within the impact energy range of E i =(0.12–1.30) eV. S 0 is independent of the adsorption temperature, T s, and the impact angle, α i, i.e., the adsorption is non-activated and total energy scaling is obeyed. The coverage, Θ, dependent adsorption probability, S(Θ), agrees with precursor-assisted adsorption dynamics (Kisliuk type) above T s ∼91K. However, below that temperature adsorbate-assisted adsorption (S increases with Θ) has been observed. That effect is most distinct at large E i and low T s. The S(Θ) data have been modeled by Monte Carlo simulations. No indications of CO2 dissociation were obtained from Auger Electron Spectroscopy or the molecular beam scattering data. [Copyright &y& Elsevier]

The structure and morphology of Co and Fe films grown on Cu(1 1 1) have been investigated by thermal energy atom scattering (TEAS) and low-energy electron diffraction (LEED). It has been found that the growth mode of Co and Fe can be greatly improved by using Pb as surfactant, although in the case of Fe this works only for the first bilayer. This shows that the two systems exhibit decisive differences already in the first stages of the growth process. In a second series of experiments, the effect of codepositing Co–Cu and Fe–Cu on the films quality was investigated. The results are very promising, and suggest that very flat, structurally ordered fcc Fe–Cu and Co–Cu films can be prepared by applying this technique together with the use of Pb as surfactant. These results were complemented by atomistic simulations based on the BFS method for alloys. Simulations performed in the low-coverage regime suggest that the early stages of growth are governed to a great extent by the affinity of Cu for Co and Fe. We have also performed temperature-dependent Monte Carlo simulations to determine the structure of superlattices formed by codeposition of Cu–Co and Cu–Fe. [Copyright &y& Elsevier]