The effect of structural changes on half-metallic, elastic and magnetic properties of the FeWGa half-Heusler compound via first-principles studies

The structural, electronical, elastical, Debye temperatures and magnetic calculations of the FeWGa half-Heusler compounds were calculated for Type I, Type II and Type III phases by using WIEN2k. The ferromagnetic state of Type II phase is energetically more stable than types. The band gaps were obtained only in Type II phase when GGA and TB_mBJ methods were used. The total magnetic moments were calculated as 1.005, 0.876, and 2.852 mu B/f.u. for Type I, Type II and Type III, respectively. However, when TB_mBJ method was used, the total magnetic moment of Type II phase was obtained as 1.00 mu B/f.u., which was compatible with Slater-Pauling rule. According to the elastically calculations, Type II and Type III phases are stable, anisotropic and ductile, while Type I phase is unstable against deformation. Then the Debye temperatures were obtained as 200.83 K, 396.11 K, and 320.34 K for Type I, Type II and Type III, respectively. The FeWGa compound has 541.29 K and 396.11 K Curie and Debye temperatures, respectively. Therefore, it is an ideal compound that can be used in spintronic applications.