The compression behaviors of zirconium from the first-principle calculations

Investigation into the structural, elastic and electronic properties for pure Zirconium (Zr) crystal has been conducted by the first-principles pseudopotential method based on density functional theory. Both methods, Local Density Approximation and Generalized Gradient Approximation, have been applied on the geometrical optimization of pure Zr to address the difference between two methods and their applicabilities. The result elucidates LDA can match the experimental data better, compared with GGA. What's more, the structural properties under pressure have been stimulated and analyzed, showing crystal lattice parameters and crystal volume change nonlinearly within the external pressure. In contrast, the single point energy of Zr shows a great linear correlation with pressure. The elastic constants of the pure Zr were calculated, proving that Zr will acquire excellent ductibility and mechanical stability under pressure. In addition, the optical properties of zirconium under different pressures were analysed. The adsorbing coefficient increases with increasing pressure. (authors)