P - V - T equation of state of synthetic mirabilite (Na 2 SO 4 ·10D 2 O) determined by powder neutron diffraction
P - V - T equation of state of synthetic mirabilite (Na 2 SO 4 ·10D 2 O) determined by powder neutron diffraction
复制标题
粉末中子衍射测定合成芒硝(Na 2 SO 4 ·10D 2 O)的P-V-T状态方程
DOI：
10.1107/s0021889813001362
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发表时间：
2013
影响因子：
6.1
通讯作者：
Fortes A
中科院分区：
文献类型：
--
作者：
Fortes A
中子粉末衍射数据是从Na_2SO_4·10D_2O（芒硝的氘代类似物）中收集的，Na_2SO_4·10D_2O是一种高度水合的硫酸盐，被认为是外太阳系一些冰卫星中的候选成岩矿物。这些测量是在ISIS中子源上使用OSIRIS仪器进行的，覆盖了0.1 < P < 545 MPa和150 < T < 270 K的范围。 作为压力和温度的函数的细化单胞体积参数化的形式的Birch-Murnaghan三阶状态方程，和各向异性的线性不可压缩性表示的弹性应变张量。在270 K时，体积模量K 0，270 = 19.6（1）GPa，其一阶压力导数K/P = 5.8（5），其温度依赖性K/T = −0.0175（6）GPa K−1。 在270 K时的最硬方向，线性体积模量为1.82 GPa，与该单斜晶体的二重轴重合。 在其余两个主方向中，最可压缩的（K = 44 GPa）大致与c轴对齐，中间值（K = 59 GPa）因此与a* 近似共线。 借助其他已发表的数据，还导出了一些其他重要的热力学量，包括格吕奈森参数和安德森-格吕奈森参数，以及沿着高压熔化曲线的熔化体积和熔化焓。在这项工作中获得的其他数据，关于氘冰IV的弹性性能，也提出了。
Neutron powder diffraction data have been collected from Na2SO4·10D2O (the deuterated analogue of mirabilite), a highly hydrated sulfate salt that is thought to be a candidate rock-forming mineral in some icy satellites of the outer solar system. These measurements, made using the OSIRIS instrument on the ISIS neutron spallation source, covered the range 0.1 < P < 545 MPa and 150 < T < 270 K. The refined unit-cell volumes as a function of pressure and temperature are parameterized in the form of a Birch–Murnaghan third-order equation of state, and the anisotropic linear incompressibilities are represented in terms of the elastic strain tensor. At 270 K, the bulk modulus K0,270 = 19.6 (1) GPa, its first pressure derivative ∂K/∂P = 5.8 (5) and its temperature dependence ∂K/∂T = −0.0175 (6) GPa K−1. The stiffest direction at 270 K, with a linear bulk modulus of ∼82 GPa, is coincident with the twofold axis of this monoclinic crystal. Of the remaining two principal directions, the most compressible (K ≃ 44 GPa) is roughly aligned with the c axis, and the intermediate value (K ≃ 59 GPa) is therefore approximately collinear with a*. With the aid of additional published data, a number of other important thermodynamic quantities have been derived, including the Grüneisen and Anderson–Grüneisen parameters, and the volume and enthalpy of melting along the high-pressure melting curve. Additional data obtained during this work, concerning the elastic properties of deuterated ice IV, are also presented.