Click here to view fulltext PDF

Permanent link:
https://www.ias.ac.in/article/fulltext/boms/035/04/0665-0672

Thermodynamic properties; elastic properties; MgSiO₃ post-perovskite.

The structure, thermodynamic and elastic properties of magnesium silicate (MgSiO₃) post-perovskite at high pressure are investigated with quasi-harmonic Debye model and ab initio method based on the density functional theory (DFT). The calculated structural parameters of MgSiO₃ post-perovskite are consistent with the available experimental results and the recent theoretical results. The Debye temperature, heat capacity and thermal expansion coefficient at high pressures and temperatures are predicted using the quasi-harmonic Debye model. The elastic constants are calculated using stress–strain relations. A complete elastic tensor of MgSiO₃ post-perovskite is determined in the wide pressure range. The calculated elastic anisotropic factors and directional bulk modulus show that MgSiO₃ post-perovskite possesses high elastic anisotropy.

Zi-Jiang Liu^{1 2} Xiao-Wei Sun² Cai-Rong Zhang³ Jian-Bu Hu⁴ Ling-Cang Cai⁴ Qi-Feng Chen⁴

1. Department of Physics, Lanzhou City University, Lanzhou 730070, China
2. School of Mathematics and Physics, Lanzhou Jiaotong University, Lanzhou 730070, China
3. State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials, Lanzhou University of Technology, Lanzhou 730050, China
4. Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics, Academy of Engineering Physics, PO Box 919-102, Mianyang 621900, China

Manuscript received

1 May 2011