Ab-initio calculations of the formation energies of BCC-based superlattices in the FeAl system

First-principles calculations of the total energies of A2 iron and aluminum, B2 (FeAl), B32 (FeAl) and D03 (Fe3Al and FeAl3) compounds were performed in the frame of density functional theory (DFT) using the Full Potential - Linear Augmented Plane Wave method (FP-LAPW). These results have been used to obtain formation energies of the respective ground states. The calculated formation energies of the D03 (Fe3Al) and B2 (FeAl) compounds show excellent agreement with available calorimetric data on standard enthalpies of formation of FeAl alloys up to 50 at.% aluminum. As the FeAl system has a controversial magnetic behavior when described by ab-initio methods in the DFT, this agreement is remarkable.