Article
Geochemistry & Geophysics
Takayuki Ishii, Artem Chanyshev, Tomoo Katsura
Summary: The Clapeyron slope is essential for understanding mantle dynamics and evolution. Previous experiments had issues in accurately determining phase boundaries. A recent study developed a novel approach using X-ray diffraction intensity, providing an accurate and precise phase boundary.
Article
Materials Science, Multidisciplinary
Pratik Kr. Das, Sudip Kumar Mondal, Nibir Mandal, A. Arya
Summary: Motivated by the wide-band-gap semiconductor properties of Zn-monochalcogenides (Zn-X; X:S, Se and Te), this study investigates the B3 to B1 structural transitions in this series of compounds as a function of pressure and temperature using a first-principles approach. The results show that the transition pressure steadily decreases from ZnS to ZnTe. The study also explores how the B3-B1 phase transitions affect the mechanical and electronic properties of Zn-X.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Binbin Yue, Matthias Krug, Carmen Sanchez-Valle, Sebastien Merkel, Fang Hong
Summary: Many MO2 compounds undergo a structural transformation from rutile to CaCl2 under high pressure. In this study, they used MnO2 as a representative system to investigate the deformation behavior and slip systems of CaCl2-structured dioxides. The study found that pressure has a significant effect on the deformation behavior and slip systems, and MnO2 transforms back to rutile upon pressure release.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Multidisciplinary Sciences
Junwei Li, Yanhao Lin, Thomas Meier, Zhipan Liu, Wei Yang, Ho-kwang Mao, Shengcai Zhu, Qingyang Hu
Summary: This study investigates the incorporation of water in stishovite using a high-dimensional neuronetwork potential and machine learning algorithm. The researchers found that stishovite and water prefer to form medium- to long-range ordered superstructures with one-dimensional water channels. By synthesizing hydrous stishovite crystals, they confirmed the ordering of OH- groups in the water channels through spectroscopy and observed fluid-like behavior of H atoms upon heating, leading to an exotic 1D superionic state.
Article
Materials Science, Multidisciplinary
G. Alexander Smith, Daniel Schacher, Jasmine K. Hinton, Daniel Sneed, Changyong Park, Sylvain Petitgirard, Keith Lawler, Ashkan Salamat
Summary: The study confirms the anomalous behavior of GeO2 during the rutile to CaCl2 phase transition, with density functional theory calculations showing a decrease in enthalpic barrier to oxygen displacements with increasing pressure, leading to the formation of small polarons in the distorted state band structure.
Article
Chemistry, Multidisciplinary
Petr S. Sokolov, Alexandre Courac, Vladimir L. Solozhenko
Summary: This study reports a method for synthesizing single-phase rs-ZnO from microcrystalline w-ZnO using a multi-anvil apparatus and pyrolytic boron nitride as a pressure medium. It was found that the metastable rs-ZnO can be completely recovered under specific compression conditions. The research also achieved a record thermal stability and Vickers hardness for the nanostructured bulk ZnO by combining appropriate compression conditions and pressure medium.
Article
Materials Science, Multidisciplinary
Mahach N. Magomedov
Summary: It is shown that the Clausius-Clapeyron relation only determines the maximum slope of the first-order phase transition line in temperature-pressure coordinates due to its irreversibility. An inequality, known as the Clausius-Clapeyron inequality, is derived to generalize the relation to irreversible phase transitions. Experimental data analysis reveals that the majority of phase transitions follow the inequality, with a greater deviation from the Clausius-Clapeyron relation observed for larger volume changes during the phase transition. The deviation from the relation is found to correlate with the presence of phase-transition radiation, making it possible to use it as a thermodynamic indication of the probability of observing such radiation in different substances. A method is proposed to estimate the irreversibility of the phase transition based on the magnitude of the deviation from the Clausius-Clapeyron relation. The generalized Clausius-Clapeyron inequality is extended to the presence of an external homogeneous magnetic or electric field acting on the two phases of matter in equilibrium.
Article
Nanoscience & Nanotechnology
I. Gordeev, L. Kolotova, S. Starikov
Summary: The mechanism of crystallization of Al-Si alloy from an amorphous state is still unclear. This study investigates the properties of aluminum silicide Al2Si structure and reveals the existence of several crystal structures with similar geometry and low formation energies. The chemical ordering in these structures is similar to that in Si-Al melt.
SCRIPTA MATERIALIA
(2022)
Article
Chemistry, Multidisciplinary
Petr S. Sokolov, Alexandre Courac, Vladimir L. Solozhenko
Summary: In this study, the conditions for synthesizing single-phase rock-salt zinc oxide (rs-ZnO) from microcrystalline wurtzite ZnO (w-ZnO) powder were reported. It was found that 3-axial decompression is a more efficient tool for reproducible recovery of high-pressure ZnO-based materials. The experimental results demonstrated that with the combination of appropriate compression conditions and pressure medium, record thermal stability and hardness of single-phase nanostructured rs-ZnO can be achieved.
Article
Geosciences, Multidisciplinary
Biao Wang, Johannes Buchen, Alba San Jose Mendez, Alexander Kurnosov, Giacomo Criniti, Hanns-Peter Liermann, Hauke Marquardt
Summary: The stishovite to post-stishovite phase transition in rocks in the Earth's lower mantle may modify the scattering of seismic waves. Compression experiments on sintered polycrystalline stishovite show that the phase transition shifts to lower pressures with increasing stress. The bulk modulus of sintered polycrystalline stishovite differs from single crystal measurements and decreases at the phase transition.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Bowen Chen, Wenzhong Wang, Zhongqing Wu, Xiaoping Wu
Summary: This study reports on first-principles results for Si and O diffusions in stishovite and CaCl2-type silica, and evaluates the viscosity of the oceanic crust under lower-mantle conditions. The results show enhanced Si diffusion in CaCl2-type silica under pressure, with a negative activation volume. Compared to bridgmanite, CaCl2-type silica exhibits two orders of magnitude faster Si diffusion, making it rheologically weaker. It can substantially reduce the crustal viscosity and facilitate the segregation of upper oceanic crust from the lower lithosphere.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Chang Su, Yonggang Liu, Dawei Fan, Wei Song, Jiyi Jiang, Zhenjun Sun, Guang Yang
Summary: The self-consistent molar volumes, elastic properties, and thermodynamic properties of beta-(Mg-0.87,Fe-0.13)(2)SiO4 wadsleyite have been determined based on an iterative numerical approach and experimental data. The results agree with available experimental and theoretical results. The thermodynamic properties of alpha-(Mg-0.9,Fe-0.1)(2)SiO4 were also investigated and compared with beta-(Mg-0.87,Fe-0.13)(2)SiO4.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geochemistry & Geophysics
Wen-Pin Hsieh, Enrico Marzotto, Yi-Chi Tsao, Takuo Okuchi, Jung-Fu Lin
Summary: Thermal transport in subducted slabs and mantle is crucial for their thermo-chemical evolution and dynamics. This study investigates the high-pressure thermal conductivities of stishovite and new-hexagonal-aluminous (NAL) phase, and their impacts on slab dynamics. The findings suggest that subducted crustal materials, especially those with local silica-enrichment, have efficient thermal conduction, leading to faster warming of the sinking slab and altering its dynamic stability.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Giacomo Criniti, Takayuki Ishii, Alexander Kurnosov, Konstantin Glazyrin, Tiziana Boffa Ballaran
Summary: The possibility of hydrogen substitution in stishovite is still debated, while the effect of aluminum incorporation has been confirmed. Experimental results suggest that the presence of hydrogen may cause different phase transition behavior in Al-bearing silica samples compared to pure silica samples.
AMERICAN MINERALOGIST
(2023)
Article
Materials Science, Multidisciplinary
Alina Nitsenko, Valeriy Volodin, Xeniya Linnik, Nurila Burabayeva, Sergey Trebukhov
Summary: The boundaries of liquid and vapor coexistence fields were determined at pressures of 101.3 and 0.133 kPa for the Al-Al2Se3 and Al2Se3-Se partial systems. The vapor pressures of aluminum selenide and selenium were determined using the boiling-point method. The purification of aluminum and distillation of selenium were found to be achievable through vacuum distillation.
Article
Geosciences, Multidisciplinary
Denis Andrault
COMPTES RENDUS GEOSCIENCE
(2019)
Article
Materials Science, Multidisciplinary
D. Freitas, G. Manthilake, J. Chantel, M. A. Bouhifd, D. Andrault
PHYSICS AND CHEMISTRY OF MINERALS
(2019)
Article
Geochemistry & Geophysics
G. Manthilake, J. Chantel, J. Monteux, D. Andrault, M. A. Bouhifd, N. Bolfan Casanova, E. Boulard, N. Guignot, A. King, J. P. Itie
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2019)
Article
Geochemistry & Geophysics
J. Monteux, D. Andrault, M. Guitreau, H. Samuel, S. Demouchy
GEOPHYSICAL JOURNAL INTERNATIONAL
(2020)
Article
Materials Science, Multidisciplinary
D. Andrault, G. Morard, G. Garbarino, M. Mezouar, M. A. Bouhifd, T. Kawamoto
PHYSICS AND CHEMISTRY OF MINERALS
(2020)
Article
Multidisciplinary Sciences
Christopher Langrand, Denis Andrault, Stephanie Durand, Zuzana Konopkova, Nadege Hilairet, Christine Thomas, Sebastien Merkel
NATURE COMMUNICATIONS
(2019)
Article
Multidisciplinary Sciences
Longjian Xie, Akira Yoneda, Daisuke Yamazaki, Geeth Manthilake, Yuji Higo, Yoshinori Tange, Nicolas Guignot, Andrew King, Mario Scheel, Denis Andrault
NATURE COMMUNICATIONS
(2020)
Article
Multidisciplinary Sciences
Guillaume Morard, Jean-Alexis Hernandez, Marco Guarguaglini, Riccardo Bolis, Alessandra Benuzzi-Mounaix, Tommaso Vinci, Guillaume Fiquet, Marzena A. Baron, Sang Heon Shim, Byeongkwan Ko, Arianna E. Gleason, Wendy L. Mao, Roberto Alonso-Mori, Hae Ja Lee, Bob Nagler, Eric Galtier, Dimosthenis Sokaras, Siegfried H. Glenzer, Denis Andrault, Gaston Garbarino, Mohamed Mezouar, Anja K. Schuster, Alessandra Ravasio
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2020)
Article
Geosciences, Multidisciplinary
Longjian Xie, Akira Yoneda, Tomoo Katsura, Denis Andrault, Yoshinori Tange, Yuji Higo
Summary: Research suggests that the persistence of primitive reservoirs in the Earth's lower mantle indicates heterogeneity. Low viscosity favors fractional solidification and chemical layering in the early mantle, potentially a source of heterogeneity in the modern mantle.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Editorial Material
Materials Science, Multidisciplinary
Denis Andrault, L. Pison, G. Morard, G. Garbarino, M. Mezouar, M. A. Bouhifd, T. Kawamoto
Summary: The additional work using laser heating in the diamond anvil cell system reveals a systematic bias in the previous determination of temperature. Two corrections applied significantly lower the melting temperature of SiO2. Reevaluation of the melting temperature profile does not affect the previous interpretations and conclusions greatly.
PHYSICS AND CHEMISTRY OF MINERALS
(2022)
Article
Geochemistry & Geophysics
Remy Pierru, Laure Pison, Antoine Mathieu, Emmanuel Gardes, Gaston Garbarino, Mohamed Mezouar, Louis Hennet, Denis Andrault
Summary: The melting properties of the deep mantle are still controversial due to experimental difficulties. In this study, new experimental determinations of the solidus profiles of ultra-dry pyrolite and (Mg,Fe)(Si,Al)O-3 bridgmanite were performed using a laser heated diamond anvil cell. The melting was detected through various methods and the influence of factors such as wavelength-dependent thermal emission and sample temperature determination were discussed. The experimental results are in good agreement with previous theoretical calculations and shock wave experiments.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Multidisciplinary Sciences
Remy Pierru, Denis Andrault, Geeth Manthilake, Julien Monteux, Jean Luc Devidal, Nicolas Guignot, Andrew King, Laura Henry
Summary: This study identifies suitable mantle conditions for different types of lava based on experimental research on pyrolite melting. A geodynamical model is developed to explain the origin of hot mantle plumes capable of generating these melting conditions.
Article
Geochemistry & Geophysics
J. Monteux, B. Qaddah, D. Andrault
Summary: The thermal convection in a terrestrial magma ocean prevents sedimentation of solid grains. Understanding the dynamics of solid phase segregation is important for studying solidification mechanisms in the early Earth mantle. Numerical models show that the ability of crystal fraction to disperse or sediment depends on crystal size, density difference, and magma viscosity. Crystal segregation is unlikely to occur in a mantle of pyrolite composition, but is more likely with SiO2-enriched ocean bottoms.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Geochemistry & Geophysics
H. Rizo, D. Andrault, N. R. Bennett, M. Humayun, A. Brandon, I Vlastelic, B. Moine, A. Poirier, M. A. Bouhifd, D. T. Murphy
GEOCHEMICAL PERSPECTIVES LETTERS
(2019)
Article
Geochemistry & Geophysics
D. Andrault, M. Munoz, G. Pesce, V Cerantola, A. Chumakov, I Kantor, S. Pascarelli, R. Ruffer, L. Hennet
GEOCHEMICAL PERSPECTIVES LETTERS
(2018)