A. A. Katsnelson

On the characteristic structural clustering in metal-metalloid amorphous systems

Abstract A Voronoi analysis of selected Feue5f8B, Feue5f8P, Niue5f8B and Niue5f8P amorphous alloys is made. The alloys were modeled by molecular dynamics, using pseudo- and Morse-pair potentials. Characteristic properties of the cluster formation are discussed.

The microstructure of liquid and amorphous aluminum

Abstract Pair correlation and the microgeometry of liquid and amorphous aluminum is calculated by molecular dynamics. The development of fivefold symmetries in microarrangements varied by the applied potential function is investigated. A stronger preference was observed for fivefold clustering using the pseudopotential approximation than in the case of the Lennard-Jones potential. A discussion of this effect is given.

On the structural and magnetic properties of amorphous Fe84−xWxB16 alloys in dependence of W content

A series of rapidly solidificated amorphous Fe84−xWxB16 (x=0–5) alloys have been studied. A strictly linear decrease ofHeff versus concentration of W has been observed by Mössbauer spectroscopy.

Changes in AlMgSi surface layers at different temperatures

Abstract It is possible to determine temperature ranges caused by electron beams under high voltage conditions. Combining the radiation power of the SXES equipment with the DTA curves we were able to make conclusions concerning the temperature range during the radiation time. Heat treatments under vacuum and continuous SXES measurements show a shift of the Fermi level and a change in the fine structure of the AlMgSi surface.

Ionization Potentials of Fe Microclusters

Ionization potentials of small iron clusters have been obtained within the local spin-density approximation and model “atom in jellium”. The nonmonotonic character of the size-dependence of an ionization energy with a cluster size has been shown.

Investigation of the Stable Structures of Nix Fex, Nix−yPy, Nix−yBy, Fex−yPy, and Fex−yBy (x =13,y<13) Microclusters

Computer simulation of the structure of Nix, Fex, Nix−yPy, Nix−yBy, Fex−yPy, Fex−yBy clusters has been carried out by molecular dynamics simulation using empirical potentials of interaction. Results indicate that the symmentry of the clusters changes with increasing of number of metalloid atoms (y). A surprising result is that when the Stillinger-Weber potential is used the great majority of the Morse minima are not supported.

Calculation of the electronic structure and magnetic properties of iron microclusters

Calculations of a spin-polarized electronic structure and magnetic moment of small iron clusters within the framework of the local spin-density approach and the model “atom in jellium” have been presented. It is shown that the occupation of localized d-states of atoms in iron clusters changes nonmonotonically depending on the atom position in relation to the cluster surface as well as on the cluster size. The nonmonotonic change of the electronic structure results in the nonmonotonic size dependence of iron cluster magnetic properties.

On the electronic states of metalloid atoms in metal-metalloid systems

Abstract The electronic structure of the metalloids B and P in Ni and Fe metallic matrices is calculated by the LAPW method. The effect of different arrangements of nearest neighbourhood and the actual charge transfers are also calculated.