Structural changes in liquids at high pressures can be observed by shock compression

Scilight ◽  
2019 ◽  
Vol 2019 (52) ◽  
pp. 521104
Author(s):  
Anashe Bandari
Keyword(s):  
Shock Compression ◽  
Structural Changes ◽  
High Pressures

scholarly journals Structural changes in thermoelectric SnSe at high pressures

2015 ◽  
Vol 27 (7) ◽  
pp. 072202 ◽  
Author(s):  
I Loa ◽  
R J Husband ◽  
R A Downie ◽  
S R Popuri ◽  
J-W G Bos
Keyword(s):  
Structural Changes ◽  
High Pressures

scholarly journals Extreme pressure conditions of bas based materials: Detailed study of structural changes, band gap engineering, elastic constants and mechanical properties

2019 ◽  
Vol 13 (4) ◽  
pp. 401-410
Author(s):  
Dejan Zagorac ◽  
Jelena Zagorac ◽  
Klaus Doll ◽  
Maria Cebela ◽  
Branko Matovic
Keyword(s):  
Mechanical Properties ◽  
Band Gap ◽  
Elastic Constants ◽  
Density Functional ◽  
Structural Changes ◽  
High Pressures ◽  
Local Density ◽  
Structure Property ◽  
Generalized Gradient ◽  
Band Gap Engineering

A Density Functional Theory (DFT) study has been performed in order to investigate behaviour of barium sulfide (BaS) at high pressures, and relationship between computed properties, in great detail. Novel predicted and previously synthesized BaS modifications have been calculated using Local Density Approximations (LDA) and Generalized Gradient Approximation (GGA) functionals. In particular, a detailed investigation of structural changes and its corresponding volume effect up to 100GPa, with gradual pressure increase, has been performed from the first principles. Band gap engineering of the experimentally observed BaS phases at high pressures has been simulated and structure-property relationship is investigated. For each of the predicted and experimentally observed BaS structures, elastic constants and mechanical properties under compression have been investigated (e.g. ductility/brittleness, hardness, anisotropy). This study offers a new perspective of barium sulphide as a high pressure material with application in ceramics, optical and electrical technologies.

Structural stability of WS2 under high pressure

2014 ◽  
Vol 28 (25) ◽  
pp. 1450168 ◽  
Author(s):  
Nirup Bandaru ◽  
Ravhi S. Kumar ◽  
Jason Baker ◽  
Oliver Tschauner ◽  
Thomas Hartmann ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
High Temperature ◽  
Structural Changes ◽  
High Pressures ◽  
Structural Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diamond Anvil ◽  
Heating Up

Structural behavior of bulk WS 2 under high pressure was investigated using synchrotron X-ray diffraction and diamond anvil cell up to 52 GPa along with high temperature X-ray diffraction and high pressure Raman spectroscopy analysis. The high pressure results obtained from X-ray diffraction and Raman analysis did not show any pressure induced structural phase transformations up to 52 GPa. The high temperature results show that the WS 2 crystal structure is stable upon heating up to 600°C. Furthermore, the powder X-ray diffraction obtained on shock subjected WS 2 to high pressures up to 10 GPa also did not reveal any structural changes. Our results suggest that even though WS 2 is less compressible than the isostructural MoS 2, its crystal structure is stable under static and dynamic compressions up to the experimental limit.

scholarly journals The Structure of Ferroselite, FeSe2, at Pressures up to 46 GPa and Temperatures down to 50 K: A Single-Crystal Micro-Diffraction Analysis

Crystals ◽  
2018 ◽  
Vol 8 (7) ◽  
pp. 289 ◽  
Author(s):  
Barbara Lavina ◽  
Robert Downs ◽  
Stanislav Sinogeikin
Keyword(s):  
Single Crystal ◽  
Low Temperatures ◽  
Diamond Anvil Cell ◽  
Structural Changes ◽  
High Pressures ◽  
Structural Instability ◽  
Crystal Structure Analysis ◽  
Ambient Conditions ◽  
Diamond Anvil

We conducted an in situ crystal structure analysis of ferroselite at non-ambient conditions. The aim is to provide a solid ground to further the understanding of the properties of this material in a broad range of conditions. Ferroselite, marcasite-type FeSe2, was studied under high pressures up to 46 GPa and low temperatures, down to 50 K using single-crystal microdiffraction techniques. High pressures and low temperatures were generated using a diamond anvil cell and a cryostat respectively. We found no evidences of structural instability in the explored P-T space. The deformation of the orthorhombic lattice is slightly anisotropic. As expected, the compressibility of the Se-Se dumbbell, the longer bond in the structure, is larger than that of the Fe-Se bonds. There are two octahedral Fe-Se bonds, the short bond, with multiplicity two, is slightly more compressible than the long bond, with multiplicity four; as a consequence the octahedral tetragonal compression slightly increases under pressure. We also achieved a robust structural analysis of ferroselite at low temperature in the diamond anvil cell. Structural changes upon temperature decrease are small but qualitatively similar to those produced by pressure.

scholarly journals In situ X-ray diffraction of silicate liquids and glasses under dynamic and static compression to megabar pressures

2020 ◽  
Vol 117 (22) ◽  
pp. 11981-11986 ◽  
Author(s):  
Guillaume Morard ◽  
Jean-Alexis Hernandez ◽  
Marco Guarguaglini ◽  
Riccardo Bolis ◽  
Alessandra Benuzzi-Mounaix ◽  
...  
Keyword(s):  
Structural Changes ◽  
High Pressures ◽  
Silicate Glasses ◽  
X Ray Diffraction ◽  
Static Compression ◽  
X Ray ◽  
Mantle Boundary ◽  
Core Mantle Boundary ◽  
Silicate Liquids

Properties of liquid silicates under high-pressure and high-temperature conditions are critical for modeling the dynamics and solidification mechanisms of the magma ocean in the early Earth, as well as for constraining entrainment of melts in the mantle and in the present-day core–mantle boundary. Here we present in situ structural measurements by X-ray diffraction of selected amorphous silicates compressed statically in diamond anvil cells (up to 157 GPa at room temperature) or dynamically by laser-generated shock compression (up to 130 GPa and 6,000 K along the MgSiO3glass Hugoniot). The X-ray diffraction patterns of silicate glasses and liquids reveal similar characteristics over a wide pressure and temperature range. Beyond the increase in Si coordination observed at 20 GPa, we find no evidence for major structural changes occurring in the silicate melts studied up to pressures and temperatures exceeding Earth’s core mantle boundary conditions. This result is supported by molecular dynamics calculations. Our findings reinforce the widely used assumption that the silicate glasses studies are appropriate structural analogs for understanding the atomic arrangement of silicate liquids at these high pressures.

The influence of high pressures on structural changes of some minerals

1997 ◽  
Vol 46 (1) ◽  
pp. 33-40
Author(s):  
Nenad M. Sˇusˇić ◽  
Aleksandar D. Spasojević ◽  
Predrag S. Polić
Keyword(s):  
Structural Changes ◽  
High Pressures

scholarly journals Phase Transitions in Natural Vanadinite at High Pressures

Minerals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1217
Author(s):  
Yingxin Liu ◽  
Liyun Dai ◽  
Xiaojing Lai ◽  
Feng Zhu ◽  
Dongzhou Zhang ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
High Pressure ◽  
Structural Changes ◽  
High Pressures ◽  
Color Change ◽  
X Ray Diffraction ◽  
Grüneisen Parameters ◽  
Reversible Phase Transition ◽  
Diamond Anvil ◽  
Gruneisen Parameters

The structural stability of vanadinite, Pb5[VO4]3Cl, is reported by high-pressure experiments using synchrotron radiation X-ray diffraction (XRD) and Raman spectroscopy. XRD experiments were performed up to 44.6 GPa and 700 K using an externally-heated diamond anvil cell (EHDAC), and Raman spectroscopy measurements were performed up to 26.8 GPa at room temperature. XRD experiments revealed a reversible phase transition of vanadinite at 23 GPa and 600 K, which is accompanied by a discontinuous volume reduction and color change of the mineral from transparent to reddish during compression. The high-pressure Raman spectra of vanadinite show apparent changes between 18.0 and 22.8 GPa and finally become amorphous at 26.8 GPa, suggesting structural transitions of this mineral upon compression. The structural changes can be distinguished by the emergence of a new vibrational mode that can be attributed to the distortion of [VO4] and the larger distortion of the V–O bonds, respectively. The [VO4] internal modes in vanadinite give isothermal mode Grüneisen parameters varying from 0.149 to 0.286, yielding an average VO4 internal mode Grüneisen parameters of 0.202.

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