High pressure effects on La(O,F)BiS2 single crystal using diamond anvil cell with dual-probe diamond electrodes

The (C60)n@SWNT (peapod) samples were prepared by vapor diffusion method. We performed the high pressure Raman measurements on the peapod samples by using a Mao-Bell type diamond anvil cell (DAC). In the In situ high pressure experiments, the peapod samples were exposed under UV laser line irradiation. The polymerization of C60 molecules in SWNT cave under both laser irradiation and pressure effects has been studied. The Raman spectra of the released samples from high pressure indicated that C60s form one-dimensional orthorhombic polymer. For the Raman measurements, two different excitation wavelengths were used, 325 nm laser and 830 nm laser.

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The effect of diffraction by the diamonds of a diamond-anvil cell on single-crystal sample intensities

Journal of Applied Crystallography ◽

10.1107/s0021889890005635 ◽

1990 ◽

Vol 23 (5) ◽

pp. 392-396 ◽

Cited By ~ 36

Author(s):

J. S. Loveday ◽

M. I. McMahon ◽

R. J. Nelmes

Keyword(s):

High Pressure ◽

Single Crystal ◽

Diamond Anvil Cell ◽

Structural Information ◽

Wavelength Dependence ◽

Single Crystal Sample ◽

Data Sets ◽

Crystal Sample ◽

Diamond Anvil ◽

Integrated Intensities

The integrated intensities measured in X-ray single-crystal high-pressure structural studies using a diamond-anvil cell are shown to be reduced substantially when the diamonds diffract at the same setting as the sample – by as much as 50% in some cases. The pressure and wavelength dependence of this process have been studied and also the effect of changing the beam divergence by the use of a synchrotron beam. The consequences for the accuracy of structural information derived from data sets collected at high pressure are considered and a data-collection strategy for detecting and avoiding the effects of diamond diffraction is proposed.

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Use of a miniature diamond-anvil cell in a joint X-ray and neutron high-pressure study on copper sulfate pentahydrate

IUCrJ ◽

10.1107/s2052252521010708 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Giulia Novelli ◽

Konstantin V. Kamenev ◽

Helen E. Maynard-Casely ◽

Simon Parsons ◽

Garry J. McIntyre

Keyword(s):

High Pressure ◽

Single Crystal ◽

Diffraction Data ◽

Diamond Anvil Cell ◽

Structural Parameters ◽

Structure Refinement ◽

Neutron Data ◽

X Ray ◽

Sulfate Pentahydrate ◽

Diamond Anvil

Single-crystal X-ray and neutron diffraction data are usually collected using separate samples. This is a disadvantage when the sample is studied at high pressure because it is very difficult to achieve exactly the same pressure in two separate experiments, especially if the neutron data are collected using Laue methods where precise absolute values of the unit-cell dimensions cannot be measured to check how close the pressures are. In this study, diffraction data have been collected under the same conditions on the same sample of copper(II) sulfate pentahydrate, using a conventional laboratory diffractometer and source for the X-ray measurements and the Koala single-crystal Laue diffractometer at the ANSTO facility for the neutron measurements. The sample, of dimensions 0.40 × 0.22 × 0.20 mm3 and held at a pressure of 0.71 GPa, was contained in a miniature Merrill–Bassett diamond-anvil cell. The highly penetrating diffracted neutron beams passing through the metal body of the miniature cell as well as through the diamonds yielded data suitable for structure refinement, and compensated for the low completeness of the X-ray measurements, which was only 24% on account of the triclinic symmetry of the sample and the shading of reciprocal space by the cell. The two data-sets were combined in a single `XN' structure refinement in which all atoms, including H atoms, were refined with anisotropic displacement parameters. The precision of the structural parameters was improved by a factor of up to 50% in the XN refinement compared with refinements using the X-ray or neutron data separately.

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High Pressure Behavior of Mascagnite from Single Crystal Synchrotron X-ray Diffraction Data

Crystals ◽

10.3390/cryst11080976 ◽

2021 ◽

Vol 11 (8) ◽

pp. 976

Author(s):

Paola Comodi ◽

Maximiliano Fastelli ◽

Giacomo Criniti ◽

Konstantin Glazyrin ◽

Azzurra Zucchini

Keyword(s):

High Pressure ◽

Single Crystal ◽

Room Temperature ◽

Diamond Anvil Cell ◽

Geometrical Parameters ◽

X Ray Diffraction ◽

Third Order ◽

X Ray ◽

Diamond Anvil ◽

Murnaghan Equation

High-pressure synchrotron X-ray diffraction was carried out on a single crystal of mascagnite, compressed in a diamond anvil cell. The sample maintained its crystal structure up to ~18 GPa. The volume–pressure data were fitted by a third-order Birch–Murnaghan equation of state (BM3-EOS) yielding K0 = 20.4(7) GPa, K’0 = 6.1(2), and V0 = 499(1) Å3, as suggested by the F-f plot. The axial compressibilities, calculated with BM3-EOS, were K0a = 35(3), K’0a = 7.7(7), K0b = 10(3), K’0b = 7(1), K0c = 25(1), and K’0c = 4.3(2) The axial moduli measured using a BM2-EOS and fixing K’0 equal to 4, were K0a = 52(2), K0b = 20 (1), and K0c = 29.6(4) GPa, and the anisotropic ratio of K0a:K0b:K0c = 1:0.4:0.5. The evolution of crystal lattice and geometrical parameters indicated no phase transition until 17.6 GPa. Sulphate polyhedra were incompressible and the density increase of 30% compared to investigated pressure should be attributed to the reduction of weaker hydrogen bonds. In contrast, some of them, directed along [100], were very short at room temperature, below 2 Å, and showed a very low compressibility. This configuration explains the anisotropic compressional behavior and the lowest compressibility of the a axis.

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Combined X-ray and neutron single-crystal diffraction in diamond anvil cells

Journal of Applied Crystallography ◽

10.1107/s1600576719014201 ◽

2020 ◽

Vol 53 (1) ◽

pp. 9-14 ◽

Cited By ~ 1

Author(s):

Andrzej Grzechnik ◽

Martin Meven ◽

Carsten Paulmann ◽

Karen Friese

Keyword(s):

High Pressure ◽

Data Processing ◽

Single Crystal ◽

Diamond Anvil Cell ◽

Crystal Data ◽

Structural Refinement ◽

Single Crystal Diffraction ◽

X Ray ◽

Diamond Anvil ◽

First Time

It is shown that it is possible to perform combined X-ray and neutron single-crystal studies in the same diamond anvil cell (DAC). A modified Merrill–Bassett DAC equipped with an inflatable membrane filled with He gas has been developed. It can be used on laboratory X-ray and synchrotron diffractometers as well as on neutron instruments. The data processing procedures and a joint structural refinement of the high-pressure synchrotron and neutron single-crystal data are presented and discussed for the first time.

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