First-principles calculations of mechanical and thermodynamic properties of tetragonal Be12Ti

• DOI: 10.1039/c8ra08711c
• Publication Date: 2019-02-12T12:24:39Z
• Authors: Xiankun Liu; Qijie Feng; Bin Tang; Jian Zheng; Zhou Zheng; Wei Zhou; Jiting Tian; Jing Wang
• Keywords: Pseudopotential; Shear modulus; Tetragonal crystal system; Lattice constant; Debye model

The elastic and thermodynamic properties of tetragonal Be12Ti under high temperature pressure are investigated by first-principles calculations based on pseudopotential plane-wave density functional theory (DFT) within the generalized gradient approximation (GGA) quasi-harmonic (QHA). calculated lattice parameters bulk modulus in good agreement with available experimental data. constants increase monotonously increasing pressure, stability criterion phonon dispersion calculation show that crystal satisfies mechanical dynamic applied (0-100 GPa). related such as (B), shear (G), Young's (E), Poisson's ratio (ν) also studied for polycrystalline Be12Ti; B/G value shows behaves a brittle manner, higher can significantly improve brittleness Be12Ti. anisotropy is demonstrated factors. direction-dependent dealt detail from 0 GPa to 100 GPa. dependencies relative volume, modulus, constants, heat capacity thermal expansion coefficient, well entropy obtained discussed using ranges 0-1600 K 0-100