Electronic and elastic properties of Mg7TiH16 hydrogen storage material

Structural, mechanical and electronic structure properties of Mg7TiH16 were investigated using the norm-conserving pseudo-potentials and plane waves (PP-PW) within the general gradient approximation (GGA) in the frame of density functional theory (DFT). The electronic density of states (DOS) reveals that Mg7TiH16 has a metallic character. The elastic constants of Mg7TiH16 were calculated for the first time. The Mg7TiH16 compound is found to be mechanically stable. The bulk modulus of single crystals has been derived using elastic constants. The results are discussed and compared with the calculated bulk modulus reported in the literature. Shear and Young’s moduli as well as Poisson’s ratio for ideal polycrystalline Mg7TiH16 are also calculated. According to the obtained results, Mg7TiH16 can be classified as ductile material. The shear anisotropic factors and the elastic anisotropy are also discussed. A Debye temperature of 619 K was also determined using theoretical elastic constants.