Formation energy in σ-phaseσ-phase Fe–V alloys

Author-Highlights•Site occupancies were successfully calculated, a task not done before.•Magnetic and configurational entropies have been taken into account.•Effect of temperature on the site occupancies has been calculated.

Formation energy of the σ-phaseσ-phase in the Fe–V alloy system, ΔEΔE, was computed in the full compositional range of its occurrence (∼34≤x≤∼60∼34≤x≤∼60) using the electronic band structure calculations by means of the KKR method. ΔE-valuesΔE-values were found to strongly depend on the Fe concentration, also its variation with different site occupancies was characteristic of a given lattice site. Calculated magnetic, Smagn, and configuration, Sconf, entropy contributions were used to determine sublattice occupancies for various compositions and temperatures. The results agree well with those obtained from neutron diffraction measurements.