• XIAO-WEI SUN

Articles written in Bulletin of Materials Science

• High-pressure physical properties of magnesium silicate post-perovskite from ab initio calculations

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.

• High pressure phase transitions for CdSe

The structure and pressure-induced phase transitions for CdSe are investigated using first-principles calculations. The pressure-induced phase transition sequence WZ/ZB $\to$ Rs $\to$ 𝐶𝑚𝑐𝑚 $\to$ CsCl for CdSe is drawn reasonably for the fist time, the corresponding transition pressures are 3.8, 29 and 107 GPa, respectively and the intermediate states between the 𝐶𝑚𝑐𝑚 structure and the CsCl structure should exist.

• Atomistic simulation of the structural and elastic properties of magnesite

Atomistic simulation was carried out to study the structural and elastic properties of MgCO$_3$ magnesite within the pressure range of the Earth’s mantle based on a novel force field. The lattice parameters and elasticconstants as a function of pressure up to 150 GPa are calculated. The results are in good agreement with the available experimental data and previous theoretical results, showing no phase transition over the pressure range of interest. We also found that magnesite exhibits a strong anisotropy throughout the lower mantle and that the nature of the anisotropy changes significantly with depth.

• # Bulletin of Materials Science

Volume 44, 2021
All articles
Continuous Article Publishing mode

• # Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020