在密度泛函理论的基础上,运用局域密度近似(LDA)和广义梯度近似(GGA)两种方法,并通过第一性原理等方法对锆晶体在0~50GPa下的物理性质进行了深入、系统的研究.结果表明,相比于广义梯度近似的计算结果而言,局域密度近似的计算结果和实验值更接近,但两者相差不是很大.并通过经典方法对锆晶体模拟计算了高压下的结构性质,得到的结果表明,在讨论的压强范围内,晶格参数与晶胞体积发生了非线性的变化,然而晶胞能量却随压强线性变化.通过对其相应的弹性性质的分析,发现随着压强的增大,锆晶体获得较好的延展性以及力学的稳定性.同时还得到了关于金属锆的能带结构特性及其光学性质,证实压强的改变对金属锆电子性质不会带来太大影响.
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.