Experimental thermal equation of state of B2−KCl
Experimental thermal equation of state of B2−KCl
复制标题
B2→KCl的实验热状态方程
DOI：
10.1103/physrevb.104.094107
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发表时间：
2021
影响因子：
3.7
通讯作者：
Campbell, A. J.
中科院分区：
文献类型：
--
作者：
Chidester, B. A.;Thompson, E. C.;Fischer, R. A.;Heinz, D. L.;Prakapenka, V. B.;Meng, Y.;Campbell, A. J.
碱金属卤化物通常在激光加热金刚石对顶砧实验中用作光学透明的压力传输介质和热绝缘体。这些材料的高P-T状态方程将允许它们同时用作灵敏的原位压力标记，使样品制备和数据分析更简单。KCl对于这种应用特别有用，因为它的高熔点，晶体学简单性和低电子密度是高温X射线衍射实验的理想选择。然而，这种材料的高温静态状态方程数据在压力上被限制在8 GPa。由于实验通常超过100 GPa的压力和数千开尔文，这是必要的KCl的状态方程，以实验确定在这些条件下，如果它是作为一个状态方程校准在未来。本文结合了新的高压，高温数据的B2相的KCl（高达167 GPa和2400 K）与以前发表的室温数据Dewaeleet等人。[Phys. Rev. B 85，214105（2012）PRBMDO 1098 -012110.1103/PhysRevB.85.214105]，以产生该材料的Mie-Grüneisen-Debye热状态方程。室温状态方程参数与以前报道的相似：GPa，和。热物性参数为2.9（4）和1.0（1）.虽然aof 1是预期的，但aof高于根据以前的计算、低压实验数据和现有的冲击波数据所预期的。因此，以前报道的状态方程低估了KCl在高温下的压力。
The alkali halides are often used as optically-transparent pressure-transmitting media and thermal insulators in laser-heated diamond anvil cell experiments. HighP–Tequations of state for these materials would allow them to be used simultaneously as sensitivein situpressure markers, making sample preparation and data analysis simpler. KCl is especially useful for this application because its high melting point, crystallographic simplicity, and low electron density are ideal for use in high-temperature x-ray diffraction experiments. However, the high-temperature static equation of state data for this material is limited in pressure to 8 GPa. As experiments routinely exceed 100 GPa in pressure and thousands of Kelvin, it is necessary for the equation of state of KCl to be determined experimentally at these conditions if it is to be used as an equation of state calibrant in the future. This paper combines new high-pressure, high-temperature data of the B2 phase of KCl (up to 167 GPa and 2400 K) with the previously published room-temperature data of Dewaeleet al.[Phys. Rev. B 85, 214105 (2012)PRBMDO1098-012110.1103/PhysRevB.85.214105] to produce a Mie-Grüneisen-Debye thermal equation of state for this material. The room-temperature equation of state parameters are similar to those reported previously:GPa, and. The thermal parameters,andare 2.9(4) and 1.0(1), respectively. While aof 1 is expected, theis higher than expected from previous calculations, lower pressure experimental data, and the available shockwave data. Thus, previously-reported equations of state underestimate the pressure of KCl at high temperatures.