Determinations of the high-pressure crystal structures of Sb2Te3
Determinations of the high-pressure crystal structures of Sb2Te3
复制标题
Sb2Te3 高压晶体结构的测定
DOI：
10.1088/0953-8984/24/47/475403
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发表时间：
2012-11-28
影响因子：
2.7
通讯作者：
Ma, Yanming
中科院分区：
文献类型：
--
作者：
Ma, Yanmei;Liu, Guangtao;Ma, Yanming
利用角色散同步辐射X射线粉末衍射技术，在金刚石对顶砧装置上研究了室温下52.7GPa范围内碲化锑（Sb_2 Te_3）的高压行为。三个高压阶段已被观察到，分别在约8.0 GPa，13.2 GPa和21.6 GPa以上。这些高压相的晶体结构分别为单斜七重C2/m相、八重C2/c相和无序体心立方结构（空间群Im − 3 m）。第一性原理计算很好地解释了所观察到的相变序列和压力。所有高压相的体积的压力依赖性由三阶Birch-Murnaghan状态方程描述。所有高压相都是金属相，并且根据电子态密度的计算结果，β-、γ-和δ-Sb_2Te_3的金属性依次增强。
Using the angle-dispersive synchrotron x-ray powder diffraction technique in a diamond anvil cell, the high-pressure behaviors of antimony telluride (Sb2Te3) are explored up to 52.7 GPa at room temperature. Three high-pressure phases have been observed, at about 8.0 GPa, 13.2 GPa and above 21.6 GPa, respectively. Furthermore, the crystalline structures of these high-pressure phases are determined as monoclinic sevenfold C2/m phase, eightfold C2/c phase and disordered body-centered cubic structure (space group Im − 3m) respectively. The phase-transition sequences and pressures observed are well explained by first-principles calculations. The pressure dependence of the volume of all high-pressure phases is described by a third-order Birch–Murnaghan equation of state. All the high-pressure phases are metallic and the metallic character for β-, γ- and δ-Sb2Te3 increases in turn based on the results of the electronic density of states calculated for each high-pressure phase.