High-pressure X-ray diffraction of icosahedral Al-Cu-Ru and Al-Pd-Re quasicrystals
High-pressure X-ray diffraction of icosahedral Al-Cu-Ru and Al-Pd-Re quasicrystals
复制标题
二十面体 Al-Cu-Ru 和 Al-Pd-Re 准晶的高压 X 射线衍射
DOI：
10.1080/01418619808214233
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发表时间：
1998
影响因子：
1.6
通讯作者：
S. Poon
中科院分区：
文献类型：
--
作者：
A. Sadoc;J. Itié;A. Polian;C. Berger;S. Poon
摘要：我们报道了二十面体 Al-Cu-Ru 和 Al-Pd-Re 准晶在室温、准流体静力条件下的高压下的原位 X 射线衍射结果。两种类型的准晶体在从环境压力到 35GPa 的压力范围内都保持二十面体。从而在压力下表现出显着的稳定性。相对体积变化 V/V 0 已拟合到 Murnaghan 型状态方程，因此一阶导数 B′0 = 5 时，Al-Cu-Ru 中的零压体积模量为 B 0 = 128 GPa，Al-Pd-Re 中的零压体积模量为 180 GPa。虽然 V/V 0 比率随压力增加而单调减小，但 Al-Cu-Ru 的布拉格峰宽度在 10 GPa 处呈现阶梯式加宽， Al-Pd-Re 的压力为 7·5 GPa，然后在更高压力下达到稳定状态。这可以通过稳定二十面体对称性的某些相子紊乱来解释。
Abstract We report in-situ X-ray diffraction results in icoshedral Al-Cu-Ru and Al-Pd-Re quasicrystals under a high pressure in quasihydrostatic conditions, at room temperature. Both types of quasicrystal remain icosahedral over the pressure range from ambient pressure up to 35GPa. thereby showing a remarkable stability under pressure. The relative volume change V/V 0 has been fitted to a Murnaghan-type equation of state so that the zero-pressure bulk modulus is B 0 = 128 GPa in Al-Cu-Ru and 180 GPa in Al-Pd-Re for a first derivative B′0 = 5. While V/V 0 ratio decreases monotonically with increasing pressure, the widths of the Bragg peaks show a stepped broadening at 10 GPa for Al-Cu-Ru and at 7·5 GPa for Al-Pd-Re before following a plateau behaviour at higher pressures. This is interpreted by some phason disorder which stabilizes the icosahedral symmetry.