压力导致SrZrO_3和ZnCr_2O_4结构相变第一性原理模拟研究(英文)

First-principle calculation predicting pressure-induced phase transitions in SrZrO_3 and ZnCr_2O_4

采用第一性原理基于密度泛函平面波赝势方法来详细研究了SrZrO_3和ZnCr_2O_4的结构,力学和电子性质.分别通过分析压力下SrZrO_3的能带宽度和弹性模量,我们预测SrZrO_3分别在30 GPa和20～25 GPa下发生相变.通过分析压力下ZnCr_2O_4的弹性常数,我们预测ZnCr_2O_4在25 GPa时发生相变.

The first-principle density functional theory （DFT） with the plane wave along with pseudopotential is employed to investigate the structural, mechanical and electronic properties of SrZrO3 and ZnCr2O4. Our calculated results are in good agreement with the experimental data and other theoretical studies. We predict that there is a phase transition in SrZrOa at 30 GPa from the analysis of the bandgap versus pressure, whereas the phase transition occurs between 20 and 25 GPa from the discussion of the bulk modulus dependence on pressure. From the analysis of elastic constants under high pressure, we infer that there is a phase transition in ZnCr2O4 at 25 GPa.