Lattice dynamics of solid xenon under pressure.
Lattice dynamics of solid xenon under pressure.
复制标题
压力下固体氙的晶格动力学。
DOI：
10.1103/physrevlett.88.075504
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发表时间：
2002
影响因子：
8.6
通讯作者：
B. Johansson
中科院分区：
文献类型：
--
作者：
J. K. Dewhurst;R. Ahuja;S. Li;B. Johansson
利用密度泛函微扰理论得到了fcc氙在压力下的声子谱。在准调和近似下得到的热力学性质与零压下的实验结果基本一致。从fcc相到hcp相的转变压力预计为5gpa。发现fcc结构在100 GPa的压力下是动态稳定的，超过100 GPa， X和L对称点的声子模式会变软。我们将观察到的fcc-hcp转变的缓慢动力学归因于相之间的小能量差以及fcc相的高动态稳定性。
We use density-functional perturbation theory to obtain the phonon spectrum of fcc xenon under pressure. Thermodynamic properties obtained within the quasiharmonic approximation are in fair to good agreement with experiment at zero pressure. The transition pressure from the fcc to hcp phase is predicted to occur at 5 GPa. The fcc structure is found to be dynamically stable up to a pressure of 100 GPa, beyond which the phonon modes at the X and L symmetry points soften. We attribute the observed sluggish kinetics of the fcc-hcp transition to the small energy difference between the phases as well as to the high dynamical stability of the fcc phase.