Anharmonicity and the isotope effect in superconducting lithium at high pressures: A first-principles approach

The metallization and dielectric properties of GaP were systematically studied under high pressures up to 30.2 GPa with resistivity measurements, impedance measurements and first-principles calculations. GaP was found to transform...

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First-principles calculations of the structural, elastic, electronic and optical properties of Si2P2O and Ge2P2O at high pressures

Chinese Journal of Physics ◽

10.1016/j.cjph.2018.06.028 ◽

2018 ◽

Vol 56 (5) ◽

pp. 2297-2307

Author(s):

Ruike Yang ◽

Bao Chai ◽

Qun Wei ◽

Dongyun Zhang

Keyword(s):

Optical Properties ◽

First Principles ◽

High Pressures ◽

First Principles Calculations ◽

Electronic And Optical Properties

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Thermodynamic Properties of CaSiO3 Perovskite at High Pressure and High Temperature

Zeitschrift für Naturforschung A ◽

10.1515/zna-2009-5-615 ◽

2009 ◽

Vol 64 (5-6) ◽

pp. 399-404 ◽

Cited By ~ 1

Author(s):

Zi-Jiang Liu ◽

Xiao-Ming Tan ◽

Yuan Guo ◽

Xiao-Ping Zheng ◽

Wen-Zhao Wu

Keyword(s):

Thermodynamic Properties ◽

First Principles ◽

Density Functional ◽

High Pressures ◽

Local Density ◽

Harmonic Approximation ◽

Debye Model ◽

Functional Theory ◽

Casio3 Perovskite ◽

First Time

The thermodynamic properties of tetragonal CaSiO3 perovskite are predicted at high pressures and temperatures using the Debye model for the first time. This model combines the ab initio calculations within local density approximation using pseudopotentials and a plane wave basis in the framework of density functional theory, and it takes into account the phononic effects within the quasi-harmonic approximation. It is found that the calculated equation of state is in excellent agreement with the observed values at ambient condition. Based on the first-principles study and the Debye model, the thermal properties including the Debye temperature, the heat capacity, the thermal expansion and the entropy are obtained in the whole pressure range from 0 to 150 GPa and temperature range from 0 to 2000 K.

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STRUCTURAL TRANSITIONS OF BiI3 UNDER PRESSURE

Modern Physics Letters B ◽

10.1142/s021798491250217x ◽

2012 ◽

Vol 26 (32) ◽

pp. 1250217

Author(s):

XIAO-XIAO SUN ◽

ZHI-RU REN ◽

DAO-GUANG WANG

Keyword(s):

First Principles ◽

Density Functional ◽

Structural Transition ◽

High Pressures ◽

Functional Theory ◽

High Pressure Studies ◽

Volume Collapse ◽

Pseudopotential Calculations ◽

Structural And Electronic Properties ◽

Pnma Phase

High pressure studies of BiI 3 at 0 K are performed using first-principles pseudopotential calculations within the framework of density functional theory. The calculations indicate that BiI 3 undergoes a structural transition from rhombohedral R-3 phase to monoclinic P2 1/c phase at 7 GPa which is accompanied by a 5.8% volume collapse. In addition, we find that P2 1/c phase prevails about 60 GPa range and transforms to cubic Fm-3m phase at 68 GPa, and finally takes the orthorhombic Pnma phase at high pressures up to 133 GPa. The structural and electronic properties of four competitive structures are also calculated. The analysis of density of states reveals that BiI 3 has semiconductor-metal transition at about 61 GPa, which also demonstrates the metallic nature of both Fm-3m and Pnma phases.

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Structure and Properties of Liquid Fe‐C Alloys at High Pressures by Experiments and First‐Principles Calculations

Geophysical Monograph Series - Carbon in Earth's Interior ◽

10.1002/9781119508229.ch4 ◽

2020 ◽

pp. 37-45

Author(s):

Bin Chen ◽

Jianwei Wang

Keyword(s):

First Principles ◽

High Pressures ◽

First Principles Calculations ◽

Structure And Properties

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THERMODYNAMIC PROPERTIES OF MgSiO3 POST-PEROVSKITE

Modern Physics Letters B ◽

10.1142/s0217984910022391 ◽

2010 ◽

Vol 24 (03) ◽

pp. 315-324

Author(s):

ZI-JIANG LIU ◽

XIAO-WEI SUN ◽

CAI-RONG ZHANG ◽

LI-NA TIAN ◽

YUAN GUO

Keyword(s):

Thermodynamic Properties ◽

First Principles ◽

Density Functional ◽

High Pressures ◽

Local Density ◽

Harmonic Approximation ◽

Debye Model ◽

Functional Theory ◽

High Pressures And Temperatures ◽

First Time

The thermodynamic properties of MgSiO 3 post-perovskite are predicted at high pressures and temperatures using the Debye model for the first time. This model combines with ab initio calculations within local density approximation using pseudopotentials and a plane wave basis in the framework of density functional theory, and it takes into account the phononic effects within the quasi-harmonic approximation. It is found that the calculated equation of state of MgSiO 3 post-perovskite is in excellent agreement with the latest observed values. Based on the first-principles study and the Debye model, the thermal properties including the Debye temperature, the heat capacity, the thermal expansion, and the entropy are obtained in the whole pressure range from 0 to 150 GPa and temperature range from 0 to 2000 K.

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Unexpected superhard phases of niobium triborides: first-principles calculations

RSC Advances ◽

10.1039/c6ra05162f ◽

2016 ◽

Vol 6 (54) ◽

pp. 49214-49220 ◽

Cited By ~ 3

Author(s):

Xiaofeng Li ◽

Junyi Du

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

High Pressures ◽

Density Functional Theory Calculations ◽

Search Method ◽

First Principles Calculations ◽

Functional Theory ◽

Swarm Optimization ◽

Structure Search

Using an unbiased structure search method based on particle-swarm optimization algorithms in combination with density functional theory calculations, we investigate the phase stability and electronic properties of NbB3 under high pressures.

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