Investigation of structural, electronic, mechanical, phonon and thermodynamic properties of Ti2FeX (X = Si, Ge, As, Sn ve Sb) inverse-Heusler alloys within ab-initio method

The structural, electronic, mechanical, phonon and thermodynamic properties of Ti2FeX (X = Si, Ge, As, Sn and Sb) in inverse Heusler structure have been computed using Generalized Gradient Appreciation (GGA) method within Density Functional Theory (DFT). The lattice constants calculated for these alloys are in good agreement with available data. The electronic spectra of these materials have been also calculated and evaluated. Elastic constants and shear modulus are examined by using stress-strain method. The phonon dispersion curves of considered inverse Heusler alloys have been calculated using direct method. These materials are both dynamical and mechanically stable since all phonon frequencies are positive and meets Born stability. Besides, specific heat capacities and entropies versus temperature of these materials were also calculated and evaluated using Gibbs2 code with Debye model. The Debye temperature of Ti2FeX (X = Si, Ge, As, Sn and Sb) inverse Heusler alloys were found to be as 442.01 K, 390.54 K, 241.25 K, 355.44 K and 348.56 K, respectively.