Gasketing optimized for large sample volume in the diamond anvil cell: first application to MgGeO3and implications for structural systematics of the perovskite to post-perovskite transition

2008 ◽  
Vol 41 (1) ◽  
pp. 38-43 ◽  
Author(s):  
C. David Martin ◽  
Yue Meng ◽  
Vitali Prakapenka ◽  
John B. Parise
Keyword(s):  
Perovskite Structure ◽  
Diamond Anvil Cell ◽  
Perovskite Phase ◽  
Volume Ratio ◽  
Sample Volume ◽  
X Ray Diffraction ◽  
A Value ◽  
Large Sample Volume ◽  
Diamond Anvil

Structure models of MgGeO3post-perovskite (Cmcm) are presented, along with a structure survey, demonstrating that all perovskite, post-perovskite and CaIrO3-type structures (ABX3) have specific ranges of the volume ratio between cation-centered polyhedra (VA:VB). The quality of the reported diffraction data and MgGeO3structure models is enhancedviaimplementation of a new graphite gasket for the diamond anvil cell, which stabilizes a larger sample volume, improving powder statistics during X-ray diffraction, andviathe thermal insulation required to achieve ultra-high temperatures while laser-heating samples at pressures near 100 GPa. The structure survey supports the theory that the pressure–temperature conditions under which the perovskite/post-perovskite phase transition occurs can be estimated by extrapolating the change inVA:VBto a value of 4, which corresponds to a maximum tilt ofBX6octahedra in the perovskite structure (Pbnm) where inter-octahedral anion–anion distances match the average intra-octahedral anion–anion distance. Once these short inter-octahedral distances between anions are reached in the perovskite structure, further tilting of octahedra and decrease of theVA:VBratio does not occur, driving the transition to post-perovskite structure as pressure is increased.

Incorporation of ferric iron in CaSiO3 perovskite at high pressure

1998 ◽  
Vol 62 (5) ◽  
pp. 719-723 ◽  
Author(s):  
Zhongwu Wang ◽  
T. Yagi
Keyword(s):  
Room Temperature ◽  
Diamond Anvil Cell ◽  
Ferric Iron ◽  
Perovskite Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Casio3 Perovskite ◽  
Diamond Anvil ◽  
Perovskite Type ◽  
Insight Into

AbstractSynthetic andradite (Ca3Fe2Si3O12) has been compressed to loading pressures >21 GPa and heated to ∼1000°C by a YAG laser in a Diamond Anvil Cell (DAC). After quenching to room temperature, X-ray diffraction of the sample, still held at 21 GPa, showed that andradite had transformed to a cubic perovskite type polymorph with a = 3.460(4) Å. Upon decompression the perovskite phase transformed into an amorphous phase. The density of the perovskite polymorph (Ca3Fe2Si3O12) is ∼13.6% greater than that of isochemical andradite at 21 GPa. Ferric iron replaces Ca2+ and Si4+ in the perovskite structure (Fe3+ + Fe3+ = Si4+ + Ca2+), giving a formula unit: (Ca,Fe3+)(Si,Fe3+)O3. The new Fe3+-rich Ca-perovskite may provide new insight into the controls on the electrical conductivity of the lower mantle.

scholarly journals Bulk modulus of H2O across the ice VII–ice X transition measured by time-resolved x-ray diffraction in dynamic diamond anvil cell experiments

2021 ◽  
Vol 103 (6) ◽  
Author(s):  
A. S. J. Méndez ◽  
F. Trybel ◽  
R. J. Husband ◽  
G. Steinle-Neumann ◽  
H.-P. Liermann ◽  
...  
Keyword(s):  
Bulk Modulus ◽  
Diamond Anvil Cell ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Diamond Anvil

PHASE TRANSITION IN LAYERED PEROVSKITE LIKE MANGANATE Ca3Mn2O7 UNDER HIGH PRESSURE

2001 ◽  
Vol 15 (18) ◽  
pp. 2491-2497 ◽  
Author(s):  
J. L. ZHU ◽  
L. C. CHEN ◽  
R. C. YU ◽  
F. Y. LI ◽  
J. LIU ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Diamond Anvil Cell ◽  
The Other ◽  
Layered Perovskite ◽  
X Ray Diffraction ◽  
Two Phase ◽  
X Ray ◽  
Diamond Anvil

In situ high pressure energy dispersive X-ray diffraction measurements on layered perovskite-like manganate Ca 3 Mn 2 O 7 under pressures up to 35 GPa have been performed by using diamond anvil cell with synchrotron radiation. The results show that the structure of layered perovskite-like manganate Ca 3 Mn 2 O 7 is unstable under pressure due to the easy compression of NaCl-type blocks. The structure of Ca 3 Mn 2 O 7 underwent two phase transitions under pressures in the range of 0~35 GPa. One was at about 1.3 GPa with the crystal structure changing from tetragonal to orthorhombic. The other was at about 9.5 GPa with the crystal structure changing from orthorhombic back to another tetragonal.

scholarly journals Synchrotron X-ray diffraction tomography technique using diamond anvil cell

2011 ◽  
Vol 67 (a1) ◽  
pp. C113-C113
Author(s):  
H. Liu ◽  
L. Wang ◽  
Z. Yu ◽  
L. Kong ◽  
J. Zhao ◽  
...  
Keyword(s):  
Diamond Anvil Cell ◽  
Diffraction Tomography ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diamond Anvil

Construction of laser-heated diamond anvil cell system for in situ x-ray diffraction study at SPring-8

2001 ◽  
Vol 72 (2) ◽  
pp. 1289 ◽  
Author(s):  
Tetsu Watanuki ◽  
Osamu Shimomura ◽  
Takehiko Yagi ◽  
Tadashi Kondo ◽  
Maiko Isshiki
Keyword(s):  
Diffraction Study ◽  
Diamond Anvil Cell ◽  
Cell System ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diamond Anvil ◽  
Laser Heated

scholarly journals Lab in a DAC – high-pressure crystal chemistry in a diamond-anvil cell

2019 ◽  
Vol 75 (6) ◽  
pp. 918-926 ◽  
Author(s):  
Andrzej Katrusiak
Keyword(s):  
High Pressure ◽  
Diamond Anvil Cell ◽  
Ambient Pressure ◽  
Elevated Pressure ◽  
Sample Volume ◽  
Chemical Research ◽  
New Era ◽  
New Information ◽  
Intermolecular Contacts ◽  
Diamond Anvil

The diamond-anvil cell (DAC) was invented 60 years ago, ushering in a new era for material sciences, extending research into the dimension of pressure. Most structural determinations and chemical research have been conducted at ambient pressure, i.e. the atmospheric pressure on Earth. However, modern experimental techniques are capable of generating pressure and temperature higher than those at the centre of Earth. Such extreme conditions can be used for obtaining unprecedented chemical compounds, but, most importantly, all fundamental phenomena can be viewed and understood from a broader perspective. This knowledge, in turn, is necessary for designing new generations of materials and applications, for example in the pharmaceutical industry or for obtaining super-hard materials. The high-pressure chambers in the DAC are already used for a considerable variety of experiments, such as chemical reactions, crystallizations, measurements of electric, dielectric and magnetic properties, transformations of biological materials as well as experiments on living tissue. Undoubtedly, more applications involving elevated pressure will follow. High-pressure methods become increasingly attractive, because they can reduce the sample volume and compress the intermolecular contacts to values unattainable by other methods, many times stronger than at low temperature. The compressed materials reveal new information about intermolecular interactions and new phases of single- and multi-component compounds can be obtained. At the same time, high-pressure techniques, and particularly those of X-ray diffraction using the DAC, have been considerably improved and many innovative developments implemented. Increasingly more equipment of in-house laboratories, as well as the instrumentation of beamlines at synchrotrons and thermal neutron sources are dedicated to high-pressure research.

scholarly journals Quasi-hydrostatic equation of state of silicon up to 1 megabar at ambient temperature

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Simone Anzellini ◽  
Michael T. Wharmby ◽  
Francesca Miozzi ◽  
Annette Kleppe ◽  
Dominik Daisenberger ◽  
...  
Keyword(s):  
Equation Of State ◽  
Room Temperature ◽  
Uniaxial Stress ◽  
Sample Volume ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
X Ray ◽  
Pressure Medium ◽  
Diamond Anvil ◽  
Isothermal Equation

Abstract The isothermal equation of state of silicon has been determined by synchrotron x-ray diffraction experiments up to 105.2 GPa at room temperature using diamond anvil cells. A He-pressure medium was used to minimize the effect of uniaxial stress on the sample volume and ruby, gold and tungsten pressure gauges were used. Seven different phases of silicon have been observed along the experimental conditions covered in the present study.

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