Elasticity of single-crystal NaCl under high-pressure: simultaneous measurement of x-ray inelastic scattering and diffraction
Elasticity of single-crystal NaCl under high-pressure: simultaneous measurement of x-ray inelastic scattering and diffraction
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DOI：
10.1080/08957959.2020.1806260
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发表时间：
2020-08-14
影响因子：
2
通讯作者：
Baron, Alfred Q. R.
中科院分区：
文献类型：
--
作者：
Fukui, Hiroshi;Yoneda, Akira;Baron, Alfred Q. R.
用非弹性x射线散射测量弹性波速，用x射线衍射测量密度，在相同的实验装置中测定了NaCl B1相单晶在高达20 GPa压力下的弹性刚度常数C(ij)s。由c （ij）计算的Voigt-Reuss-Hill平均速度与以前对多晶样品的超声测量结果很好地一致。提出了基于现有弹性常数和密度的绝对压力。为了拟合我们的结果，需要至少具有三个参数的状态方程（除了参考体积），例如Birch-Murnaghan方程的四阶形式或Vinet方程的高阶形式，因为较少的参数不能再现所观察到的体积和体积模量的压力依赖性。
Elastic stiffness constants,C(ij)s, of single crystal of NaCl B1 phase have been determined at pressure up to 20 GPa using inelastic x-ray scattering to measure elastic wave velocities and x-ray diffraction to measure densities in the same experimental setup. The Voigt-Reuss-Hill average velocities calculated from the presentC(ij)sare in good agreement with previous ultrasonic measurements of polycrystalline samples. Absolute pressures based on the present elastic constants and densities are proposed. In order to fit our results an equation of state with at least three parameters (an addition to a reference volume), such as the fourth-order form of Birch-Murnaghan equation or the higher order form of Vinet equation, is required, as fewer parameters do not reproduce the observed pressure dependence of the volume and bulk modulus.