Indexing of multi-particle diffraction data in a high-pressure single-crystal diffraction experiment

High-pressure single-crystal diffraction experiments often suffer from the crushing of single crystals due to the application of high pressure. Consequently, only diffraction data resulting from several particles in random orientations is available, which cannot be routinely indexed by commonly used methods designed for single-crystal data. A protocol is proposed to index such diffraction data. The techniques of powder pattern indexing are first used to propose the possible lattice parameters, and then a genetic algorithm is applied to determine the orientation of the reciprocal lattice for each of the particles. This protocol has been verified experimentally.

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High-pressure synthesis of α-PbO2 and its crystal structure at 293, 203, and 113 K from single crystal diffraction data

Solid State Sciences ◽

10.1016/j.solidstatesciences.2005.08.007 ◽

2005 ◽

Vol 7 (11) ◽

pp. 1363-1368 ◽

Cited By ~ 20

Author(s):

Stanislav Filatov ◽

Nikolay Bendeliani ◽

Barbara Albert ◽

Jürgen Kopf ◽

Tatiana Dyuzeva ◽

...

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Single Crystal ◽

Diffraction Data ◽

Single Crystal Diffraction ◽

High Pressure Synthesis ◽

Pressure Synthesis

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Structure of Ce2Pt6Ga15: interplanar disorder from the Ce2Ga3 layers

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768196000481 ◽

1996 ◽

Vol 52 (4) ◽

pp. 580-585 ◽

Cited By ~ 13

Author(s):

G. H. Kwei ◽

A. C. Lawson ◽

A. C. Larson ◽

B. Morosin ◽

E. M. Larson ◽

...

Keyword(s):

Neutron Diffraction ◽

Single Crystal ◽

Diffraction Data ◽

Diffuse Scattering ◽

Heavy Fermion ◽

Neutron Diffraction Data ◽

Crystal Data ◽

Single Crystal Diffraction ◽

X Ray ◽

A Cell

The structure of the heavy fermion compound Ce2Pt6Ga15 has been determined from neutron powder and X-ray/neutron single-crystal diffraction. Examination of symmetry equivalence among the single-crystal data, as well as the good fit of the powder data to the final structural arrangement, with all the atoms on symmetry sites, suggests that the correct space group is P63/mmc. The structure is unusual in that Ce layers have 1/3 of the Ce atoms replaced by groups of three Ga atoms; distances between atoms in these planes suggest this substitution must occur in a concerted fashion. The refined occupancies lead to a stoichiometry near Ce2Pt6Ga15, consistent with such an arrangement. In addition, single-crystal neutron diffraction data show columns of weak diffuse scattering along the <001> axes, suggesting disorder arising from a lack of registration of successive Ce2Ga3 layers (lying half a cell length or 8.27 Å apart along z) and a 3 × 3 × 1 supercell. This disorder is very likely responsible for the low resistance ratio of approximately unity measured for single-crystal samples.

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Fundamental Developments in Direct-Space Techniques for Structure Solution from Powder Diffraction Data

Materials Science Forum ◽

10.4028/www.scientific.net/msf.443-444.11 ◽

2004 ◽

Vol 443-444 ◽

pp. 11-22

Author(s):

Scott Habershon ◽

David Albesa-Jové ◽

Eugene Y. Cheung ◽

Giles W. Turner ◽

Roy L. Johnston ◽

...

Keyword(s):

Genetic Algorithm ◽

Single Crystal ◽

Powder Diffraction ◽

Diffraction Data ◽

Structure Determination ◽

Structural Investigation ◽

Powder Diffraction Data ◽

Single Crystal Diffraction ◽

R Factor ◽

Structure Solution

Solids that can be prepared only as microcrystalline powders are not suitable for structural investigation using single crystal diffraction techniques, and it is necessary instead to carry out structure determination using powder diffraction data. In this paper, we focus on a direct-space strategy for solving crystal structures directly from powder diffraction data in which a hypersurface based on the powder profile R-factor Rwp is searched using a Genetic Algorithm, and we highlight some recent fundamental developments relating to this methodology.

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High-Pressure Synthesis of α-PbO2 and Its Crystal Structure at 293, 203, and 113 K from Single Crystal Diffraction Data.

ChemInform ◽

10.1002/chin.200606007 ◽

2006 ◽

Vol 37 (6) ◽

Author(s):

Stanislav Filatov ◽

Nikolay Bendeliani ◽

Barbara Albert ◽

Juergen Kopf ◽

Tatiana Dyuzeva ◽

...

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Single Crystal ◽

Diffraction Data ◽

Single Crystal Diffraction ◽

High Pressure Synthesis ◽

Pressure Synthesis

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Notizen: Zur Kristallstruktur von SrPbO3 / The Crystal Structure of SrPbO3

Zeitschrift für Naturforschung B ◽

10.1515/znb-1975-3-428 ◽

1975 ◽

Vol 30 (3-4) ◽

pp. 277-278 ◽

Cited By ~ 11

Author(s):

Hans-L. Keller ◽

Karl-H. Meier ◽

Hk. Müller-Buschbaum

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Single Crystal ◽

Single Crystals ◽

Diffraction Data ◽

X Ray Diffraction ◽

Space Group ◽

X Ray ◽

Pressure Synthesis ◽

Group D

Single crystals of SrPbO3 could be prepared by oxygen-high-pressure-synthesis (PO2 > 3500 at, t = 450°C). Single crystal X-ray diffraction data confirm the space group D2h16-Pnma. SrPbO3 belongs to the orthorhombic distorted Perowskit type with a = 5.964, b = 8.320, c = 5.860 Å. The atomic positions were refined.

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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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Determining complex crystal structures from high pressure single-crystal diffraction data collected on synchrotron sources

High Pressure Research ◽

10.1080/08957959.2013.831087 ◽

2013 ◽

Vol 33 (3) ◽

pp. 485-500 ◽

Cited By ~ 9

Author(s):

M. I. McMahon ◽

I. Loa ◽

G. W. Stinton ◽

L. F. Lundegaard

Keyword(s):

High Pressure ◽

Single Crystal ◽

Crystal Structures ◽

Diffraction Data ◽

Single Crystal Diffraction ◽

Complex Crystal

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The polyoctahedral silsesquioxane (POSS) 1,3,5,7,9,11,13,15-octaphenylpentacyclo[9.5.1.13,9.15,15.17,13]octasiloxane (octaphenyl-POSS)

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229614019834 ◽

2014 ◽

Vol 70 (10) ◽

pp. 971-974 ◽

Cited By ~ 2

Author(s):

Parameswara Rao Chinnam ◽

Michael R. Gau ◽

Joseph Schwab ◽

Michael J. Zdilla ◽

Stephanie L. Wunder

Keyword(s):

Single Crystal ◽

Bond Length ◽

Single Crystals ◽

Gas Phase ◽

Solvent Free ◽

Powder Pattern ◽

Crystal Data ◽

Bond Angles ◽

Bond Lengths ◽

Centrosymmetric Molecule

Solvent-free single crystals of 1,3,5,7,9,11,13,15-octaphenylpentacyclo[9.5.1.13,9.15,15.17,13]octasiloxane (abbreviated as octaphenyl-POSS), C48H40O12Si8, were obtained by dehydration/condensation of the tetrol Si4O4(Ph)4(OH)4. The powder pattern generated from the single-crystal data matches well with the experimentally measured powder pattern of commercial octaphenyl-POSS. The geometry of the centrosymmetric molecule in the crystal was compared with that in the gas phase, and had shorter Si—O bond lengths and a broader range of Si—O—Si bond angles. The average Si—O bond length [1.621 (3) Å], and Si—O—Si and O—Si—O bond angles [149 (5) and 109 (1)°, respectively] were within the same range measured previously for octaphenyl-POSS solvates.

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Refinement of high pressure single-crystal diffraction data using Jana2006

High Pressure Research ◽

10.1080/08957959.2012.758723 ◽

2013 ◽

Vol 33 (1) ◽

pp. 196-201 ◽

Cited By ~ 14

Author(s):

K. Friese ◽

A. Grzechnik ◽

J. M. Posse ◽

V. Petricek

Keyword(s):

High Pressure ◽

Single Crystal ◽

Diffraction Data ◽

Single Crystal Diffraction

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Ind_X: program for indexing single-crystal diffraction patterns

Journal of Applied Crystallography ◽

10.1107/s1600576717000516 ◽

2017 ◽

Vol 50 (2) ◽

pp. 647-650 ◽

Cited By ~ 2

Author(s):

A. Morawiec

Keyword(s):

Single Crystal ◽

Diffraction Data ◽

Reciprocal Lattice ◽

Primitive Cell ◽

Single Crystal Diffraction ◽

Test Volume ◽

Lattice Matching ◽

Essential Step ◽

Testing Potential ◽

Diffraction Patterns

Indexing is an essential step in analysis of diffraction patterns. Diffraction of monochromatic radiation by a single crystal provides approximate positions of some nodes of the reciprocal lattice of the crystal, and the indexing problem lies in determining a lattice matching these positions. Ind_X is a program for indexing diffraction data given in the form of several approximate reciprocal lattice nodes. The applied method relies on testing potential volumes of the primitive cell of the reciprocal lattice. A subset of reciprocal lattice vectors supporting a given test volume is used to obtain tentative lattice bases. These are bases of low-index superlattices of lattices based on triplets of supporting vectors. The Ind_X solution of the indexing problem consists of a list of best bases. The method turns out to be quite robust to data inaccuracies and spurious reflections. The program is relatively versatile, easily operated and freely accessible.

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