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We present here an experimental study of the growth of Re/W(110). Auger electron spectroscopy, core level photoelectron spectroscopy and LEED experiments at T = 500 K and as a function of Re coverage θ show first (θ < 0.5 ML) a surface reconstruction followed (θ ≈ 1 ML) by formation of a two-layer surface alloy which is then buried by additional Re-layers (θ ≈ 3 ML). An empirical model is developed to simulate the growth mode. The main effect of annealing is to increase the number of Re-enriched layers. The establishment of a surface alloy over several atomic layers introduces the new idea of local equilibrium. Finally, the extension to non equilibrium situations of the usual thermodynamical Born-Haber cycle allowed us to derive from the KTBIM the time-evolution of the W4f core level spectra and shifts in good agreement with the experimental data.

We study here the relation between the surface segregation at thermodynamical equilibrium in an alloy AcB1−c and the kinetics of either segregation in the system A-B or dissolution of AB or BA. This is possible within a new kinetic model based on the electronic structure: the kinetic tight-binding Ising model (KTBIM). In particular, the existence of a local equilibrium between the surface and the first underlayer is stressed. Some illustrations are given in the particular case of the W-Re system.

In contrast to what is commonly accepted, electronic structure calculations show that the core levels (S1, S2) associated with the surface and first underlayer atoms can be displaced in opposite directions in energy with respect to the bulk level (B). This is fully confirmed by experiments performed on the 4f 7 2 level of the Ir(100) surface, both in the unreconstructed (1 × 1) and reconstructed (5 × 1) case.

Surface EXAFS is used to determine the crystallographic structure of iron films prepared by deposition on Cu(100). These metastable films have structural and vibrational properties strongly dependent on their thickness and on their growth temperature. A well defined fee structure is obtained in films grown at a temperature higher than 350 K and in thick films (8 monolayers) grown at room temperature. The thinner films (2 to 5 monolayers) grown at room temperature do not have an fee structure: the first shell radial distribution function is very broad and anisotropic. The origin of this first shell broadening can be random static disorder in the layer or a well defined reconstruction inducing different nearest neighbour distances. These different crystallographic structures are apparently connected to the different magnetic properties measured in these films.