Electronic Structure and Magnetic Properties of Alloys

Abstract

The comparative analysis of electronic structure and magnetic properties of substitutional alloys FexCr1−x is performed by two methods — the band method of a supercell in reciprocal space and method of the recursion in direct space at different concentrations of components. In both cases, the same spin-polarized screened basis of linear muffin-tin orbitals within the atomic sphere approximation (TB–LMTO–ASA) is used. It is known, and in a given paper it is shown, that the band method allows to execute the full self-consistency, but can not eliminate the influence of periodic boundary conditions. On the contrary, the cluster method of recursion does not demand translation invariance, but within its framework it is more difficult to execute the full self-consistency. These two methods are mutually complementary and allow to obtain more information by calculation of electronic structure of disordered systems. The main difference of band calculation from cluster one is that within the latter there are localized resonance states. As a result of calculation, it is shown that with a change of concentration of components there are essential changes in electronic and magnetic structure of alloys of a system Fe–Cr. The maximum changes occur when the concentration of one of components verges towards 30%. It is noted that the area of magnetic phase transitions is congruent with the origin of phase immiscibility in a system. The magnetism disappears at a chromium concentration, which is equal to 70% and above.

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