Theoretical study of electronic properties and spin density in Pt-Co alloys

The Pt-Co alloys have been widely studied for the mechanical, magnetic and electrical properties they exhibit. Some of these properties are product of the structural changes that occur due to the differents of the atomic relationships in the alloy. The spin density and electronic properties are strongly dependent to the structural changes, for this reason it is important study the structural evolution of Pt-Co alloys. Using Density Functional Theory (DFT), applying the generalized gradient approximation for exchange and correlation (GGA), the electronic properties and the spin density in stable structures of Pt, Co, superlattice Pt3Co L10 and superlattice PtCo L12 were studied. Taking into account the structural evolution and considering the structure most stable, the results obtained showed that the concentration of Co atoms has strongly influences in the spin density and the behavior of their neighboring Pt atoms, the structure of bands with the density of states shows overlap of bands d and electrons located below the Fermi level, which is typical in the transition metals. Both spin density and deformation electron density showed relationship between bonding electrons and non-bonding in the structure through isosurfaces.