Effects of pressure on structural, mechanical, and electronic properties of trigonal and monoclinic MgSiO 3

被引：16

作者：

Gao, Juan ^{[1
]}

Zeng, Wei ^{[2
]}

Tang, Bin ^{[3
]}

Fan, Dai-He ^{[1
]}

Liu, Qi-Jun ^{[1
]}

Chang, Xiang-Hui ^{[1
]}

Zhong, Mi ^{[1
]}

机构：

[1] Southwest Jiaotong Univ, Sch Phys Sci & Technol, Key Lab Adv Technol Mat, Minist Educ China, Chengdu 610031, Sichuan, Peoples R China

[2] Chengdu Univ Tradit Chinese Med, Coll Med Technol, Teaching & Res Grp Chem, Chengdu 610075, Peoples R China

[3] Northwestern Polytech Univ, State Key Lab Solidificat Proc, Xian 710072, Peoples R China

来源：

SOLID STATE SCIENCES | 2020年 / 105卷

关键词：

AB-INITIO; THERMODYNAMIC PROPERTIES; POPULATION ANALYSIS; PHASE-TRANSITIONS; ILMENITE; AKIMOTOITE; PEROVSKITE; 1ST-PRINCIPLES; CLINOENSTATITE; STATE;

D O I：

10.1016/j.solidstatesciences.2020.106261

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

We perform the first-principles calculation based on density-functional theory (DFT) to study the structural, electronic and mechanical properties of two MgSiO3 polymorphs (trigonal R‾3 and monoclinic P21/c) under pressure. The optimized lattice parameters of two MgSiO3 polymorphs under pressure are obtained and analyzed. Comparing the enthalpy values of the two structures under pressure, we find that monoclinic MgSiO3 will translate into trigonal structure in the range of 10 GPa–20 GPa. The relationship between the band structure and pressure is revealed. And we calculate the total density of state (TDOS) under different pressures and partial density of state (PDOS) under 0 GPa. The electron populations are obtained for trigonal and monoclinic MgSiO3. We systemically studied the mechanical properties of trigonal and monoclinic MgSiO3 under pressure including elastic constants, bulk modulus, shear modulus, Lamé's constants, Young's modulus, Poisson's ratio as well as B/G values. According to the modified Born stability conditions under pressure, trigonal MgSiO3 is stable from 0 GPa to 150 GPa, but monoclinic MgSiO3 is unstable from 80 GPa to 100 GPa. © 2020 Elsevier Masson SAS

引用

页数：11

共 56 条

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