Crystal structure and elastic constants of β‐Mg2SiO4 under high pressure simulated from a potential model
Crystal structure and elastic constants of β‐Mg2SiO4 under high pressure simulated from a potential model
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势能模型模拟高压下 β-Mg2SiO4 的晶体结构和弹性常数
DOI：
10.1107/s0108768185002336
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Takeo Matsumoto
中科院分区：
文献类型：
--
作者：
M. Matsui;Takeo Matsumoto
建立了基于能量最小化的/3-MgESiO4的计算模型。该模型的势能包括非键原子之间的库仑相互作用和排斥相互作用，以及Si-O距离的键距拉伸能项和O-Si-O角度的键角弯曲能项。一些能量参数被视为a-和/3-Mg2SiO4共有的，并通过改变这些参数得到，直到计算出的a- mg2sio4的大气压结构和弹性常数与实验结果尽可能接近。导出了模拟fl-Mg2SiO4所需的其他能量参数，以再现观测到的fl-Mg2SiO4的大气压结构。所得电位模型成功地用于计算fl- Mg2SiO4的弹性常数。随后，将该模型应用于高压下fl-MgESiO4晶体结构的模拟。利用该模型计算了fl-MgESiO4弹性常数的压力导数。并将该模型与最近提出的/3Mg2SiO4模型进行了比较。
A computational model based on energy minimization has been developed for/3-MgESiO4. The potential energy of the model includes Coulomb and repulsive interactions between non-bonded atoms as well as bond-distance-stretching energy terms for Si-O distances and bond-angle-bending energy terms for O-Si-O angles. Some of the energy parameters are treated as common to a- and /3-Mg2SiO4, and are obtained by varying these parameters until both the calculated atmospheric-pressure structure and the elastic constants of a-Mg2SiO4 agree as closely as possible with the experimental ones. Other necessary energy parameters for the modeling of fl-Mg2SiO4 are derived to reproduce the observed atmosphericpressure structure of fl-Mg2SiO4. The potential model obtained is successfully used for the calculation of the elastic constants of fl- Mg2SiO4. Subsequently, the model is applied to the simulation of crystal structures of fl-MgESiO4 under high pressure. The pressure derivatives of the elastic constants of fl-MgESiO4 are also evaluated using the model. The present model is compared with a recently proposed one for /3Mg2SiO4.