外压下ZrN结构相变的第一性原理研究

First-Principles Investigations on Phase Transition of ZrN under External Pressure

利用基于密度泛函理论的赝势平面波方法,研究了面心立方（fcc）和体心立方（bcc）结构ZrN的平衡态性质以及不同压力下的弹性性质,计算了fcc和bcc结构ZrN的焓-压关系,讨论了其相对稳定性。通过对总能、焓-压关系、弹性性质以及声子色散关系的分析,推测fcc结构到bcc结构的相变发生在205-235GPa之间。

Using a plane-wave pseudo-potential density functional theory method, the equilibrium and e- lastic properties of fcc and bcc ZrN structures under different pressures were studied. The relationship between enthalpy and pressure of fcc and bcc structures was also investigated,and their relative stabil- ity was discussed. From the analysis of the relationship between the total energy,enthalpy with pres- sure,elastic properties and the phonon spectra, conclusion is found that transformation from the fce structural phase to bcc structural phase occurs at 205-235 GPa.