A curved image-plate detector system for high-resolution synchrotron X-ray diffraction

The developed curved image plate (CIP) is a one-dimensional detector which simultaneously records high-resolution X-ray diffraction (XRD) patterns over a 38.7° 2θ range. In addition, an on-site reader enables rapid extraction, transfer and storage of X-ray intensity information in ≤30 s, and further qualifies this detector to study kinetic processes in materials science. The CIP detector can detect and store X-ray intensity information linearly proportional to the incident photon flux over a dynamical range of about five orders of magnitude. The linearity and uniformity of the CIP detector response is not compromised in the unsaturated regions of the image plate, regardless of saturation in another region. The speed of XRD data acquisition together with excellent resolution afforded by the CIP detector is unique and opens up wide possibilities in materials research accessible through X-ray diffraction. This article presents details of the basic features, operation and performance of the CIP detector along with some examples of applications, including high-temperature XRD.

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A high-throughput assembly of beam-shaping channel-cut monochromators for laboratory high-resolution X-ray diffraction and small-angle X-ray scattering experiments

Journal of Applied Crystallography ◽

10.1107/s1600576721002338 ◽

2021 ◽

Vol 54 (3) ◽

Author(s):

Peter Nadazdy ◽

Jakub Hagara ◽

Petr Mikulik ◽

Zdenko Zaprazny ◽

Dusan Korytar ◽

...

Keyword(s):

High Resolution ◽

Small Angle ◽

Photon Flux ◽

Photon Flux Density ◽

X Ray Diffraction ◽

High Beam ◽

X Ray ◽

X Ray Scattering ◽

Beam Collimation ◽

Ray Scattering

A four-bounce monochromator assembly composed of Ge(111) and Ge(220) monolithic channel-cut monochromators with V-shaped channels in a quasi-dispersive configuration is presented. The assembly provides an optimal design in terms of the highest transmittance and photon flux density per detector pixel while maintaining high beam collimation. A monochromator assembly optimized for the highest recorded intensity per detector pixel of a linear detector placed 2.5 m behind the assembly was realized and tested by high-resolution X-ray diffraction and small-angle X-ray scattering measurements using a microfocus X-ray source. Conventional symmetric and asymmetric Ge(220) Bartels monochromators were similarly tested and the results were compared. The new assembly provides a transmittance that is an order of magnitude higher and 2.5 times higher than those provided by the symmetric and asymmetric Bartels monochromators, respectively, while the output beam divergence is twice that of the asymmetric Bartels monochromator. These results demonstrate the advantage of the proposed monochromator assembly in cases where the resolution can be partially sacrificed in favour of higher transmittance while still maintaining high beam collimation. Weakly scattering samples such as nanostructures are an example. A general advantage of the new monochromator is a significant reduction in the exposure time required to collect usable experimental data. A comparison of the theoretical and experimental results also reveals the current limitations of the technology of polishing hard-to-reach surfaces in X-ray crystal optics.

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MicroED: a versatile cryoEM method for structure determination

Emerging Topics in Life Sciences ◽

10.1042/etls20170082 ◽

2018 ◽

Vol 2 (1) ◽

pp. 1-8 ◽

Cited By ~ 13

Author(s):

Brent L. Nannenga ◽

Tamir Gonen

Keyword(s):

Electron Microscope ◽

High Resolution ◽

Electron Diffraction ◽

Structure Determination ◽

Materials Science ◽

Electron Diffraction Data ◽

Determination Method ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron

Micro-electron diffraction, or MicroED, is a structure determination method that uses a cryo-transmission electron microscope to collect electron diffraction data from nanocrystals. This technique has been successfully used to determine the high-resolution structures of many targets from crystals orders of magnitude smaller than what is needed for X-ray diffraction experiments. In this review, we will describe the MicroED method and recent structures that have been determined. Additionally, applications of electron diffraction to the fields of small molecule crystallography and materials science will be discussed.

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XDS: a flexible beamline for X-ray diffraction and spectroscopy at the Brazilian synchrotron

Journal of Synchrotron Radiation ◽

10.1107/s160057751601403x ◽

2016 ◽

Vol 23 (6) ◽

pp. 1538-1549 ◽

Cited By ~ 23

Author(s):

F. A. Lima ◽

M. E. Saleta ◽

R. J. S. Pagliuca ◽

M. A. Eleotério ◽

R. D. Reis ◽

...

Keyword(s):

High Pressures ◽

Materials Science ◽

Photon Flux ◽

X Ray Diffraction ◽

X Ray ◽

X Ray Scattering ◽

Science Community ◽

Synchrotron Light ◽

X Ray Absorption ◽

Photon Source

The majority of the beamlines at the Brazilian Synchrotron Light Source Laboratory (LNLS) use radiation produced in the storage-ring bending magnets and are therefore currently limited in the flux that can be used in the harder part of the X-ray spectrum (above ∼10 keV). A 4 T superconducting multipolar wiggler (SCW) was recently installed at LNLS in order to improve the photon flux above 10 keV and fulfill the demands set by the materials science community. A new multi-purpose beamline was then installed at the LNLS using the SCW as a photon source. The XDS is a flexible beamline operating in the energy range between 5 and 30 keV, designed to perform experiments using absorption, diffraction and scattering techniques. Most of the work performed at the XDS beamline concentrates on X-ray absorption spectroscopy at energies above 18 keV and high-resolution diffraction experiments. More recently, new setups and photon-hungry experiments such as total X-ray scattering, X-ray diffraction under high pressures, resonant X-ray emission spectroscopy, among others, have started to become routine at XDS. Here, the XDS beamline characteristics, performance and a few new experimental possibilities are described.

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A High Resolution Study of G.P. Zones in Aluminum - 4.2 at % Silver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055904 ◽

1982 ◽

Vol 40 ◽

pp. 722-723 ◽

Cited By ~ 1

Author(s):

R. Gronsky

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Computer Simulations ◽

Structural Characteristics ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Resolution Study

The phenomenon of clustering in Al-Ag alloys has been extensively studied since the early work of Guinierl, wherein the pre-precipitation state was characterized as an assembly of spherical, ordered, silver-rich G.P. zones. Subsequent x-ray and TEM investigations yielded results in general agreement with this model. However, serious discrepancies were later revealed by the detailed x-ray diffraction - based computer simulations of Gragg and Cohen, i.e., the silver-rich clusters were instead octahedral in shape and fully disordered, atleast below 170°C. The object of the present investigation is to examine directly the structural characteristics of G.P. zones in Al-Ag by high resolution transmission electron microscopy.

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Tubulin structure at intermediate resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140634 ◽

1995 ◽

Vol 53 ◽

pp. 852-853

Author(s):

K. H. Downing ◽

S. G. Wolf ◽

E. Nogales

Keyword(s):

High Resolution ◽

Structural Data ◽

Therapeutic Drug ◽

Zinc Ions ◽

Two Dimensional ◽

X Ray Diffraction ◽

X Ray ◽

Negative Stain ◽

Functional Mechanisms ◽

Tubulin Structure

Microtubules are involved in a host of critical cell activities, many of which involve transport of organelles through the cell. Different sets of microtubules appear to form during the cell cycle for different functions. Knowledge of the structure of tubulin will be necessary in order to understand the various functional mechanisms of microtubule assemble, disassembly, and interaction with other molecules, but tubulin has so far resisted crystallization for x-ray diffraction studies. Fortuitously, in the presence of zinc ions, tubulin also forms two-dimensional, crystalline sheets that are ideally suited for study by electron microscopy. We have refined procedures for forming the sheets and preparing them for EM, and have been able to obtain high-resolution structural data that sheds light on the formation and stabilization of microtubules, and even the interaction with a therapeutic drug.Tubulin sheets had been extensively studied in negative stain, demonstrating that the same protofilament structure was formed in the sheets and microtubules. For high resolution studies, we have found that the sheets embedded in either glucose or tannin diffract to around 3 Å.

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X-ray microprobe for materials science

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168013 ◽

1994 ◽

Vol 52 ◽

pp. 56-57

Author(s):

G.E. Ice

Keyword(s):

Crystallographic Orientation ◽

Local Structure ◽

Materials Science ◽

Chemical Information ◽

X Ray Diffraction ◽

Ray Optics ◽

X Ray ◽

Novel Materials ◽

New Information ◽

Elemental Sensitivity

The increasing availability of synchrotron x-ray sources has stimulated the development of advanced hard x-ray (E≥5 keV) microprobes. With new x-ray optics these microprobes can achieve micron and submicron spatial resolutions. The inherent elemental and crystallographic sensitivity of an x-ray microprobe and its inherently nondestructive and penetrating nature will have important applications to materials science. For example, x-ray fluorescent microanalysis of materials can reveal elemental distributions with greater sensitivity than alternative nondestructive probes. In materials, segregation and nonuniform distributions are the rule rather than the exception. Common interfaces to whichsegregation occurs are surfaces, grain and precipitate boundaries, dislocations, and surfaces formed by defects such as vacancy and interstitial configurations. In addition to chemical information, an x-ray diffraction microprobe can reveal the local structure of a material by detecting its phase, crystallographic orientation and strain.Demonstration experiments have already exploited the penetrating nature of an x-ray microprobe and its inherent elemental sensitivity to provide new information about elemental distributions in novel materials.

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High-resolution X-ray diffraction in crystalline structures with quantum dots

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0185.201505a.0449 ◽

2015 ◽

Vol 185 (5) ◽

pp. 449-478

Author(s):

Vasilii I. Punegov

Keyword(s):

Quantum Dots ◽

High Resolution ◽

X Ray Diffraction ◽

X Ray ◽

Crystalline Structures

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Dislocation Arrangement in a Thick LEO GaN Film on Sapphire

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300004130 ◽

2000 ◽

Vol 5 (S1) ◽

pp. 97-103

Author(s):

Kathleen A. Dunn ◽

Susan E. Babcock ◽

Donald S. Stone ◽

Richard J. Matyi ◽

Ling Zhang ◽

...

Keyword(s):

High Resolution ◽

Electron Diffraction ◽

Threading Dislocations ◽

X Ray Diffraction ◽

Burgers Vector ◽

X Ray ◽

The Third ◽

Dislocation Arrangement ◽

Image Position ◽

Gan Film

Diffraction-contrast TEM, focused probe electron diffraction, and high-resolution X-ray diffraction were used to characterize the dislocation arrangements in a 16µm thick coalesced GaN film grown by MOVPE LEO. As is commonly observed, the threading dislocations that are duplicated from the template above the window bend toward (0001). At the coalescence plane they bend back to lie along [0001] and thread to the surface. In addition, three other sets of dislocations were observed. The first set consists of a wall of parallel dislocations lying in the coalescence plane and nearly parallel to the substrate, with Burgers vector (b) in the (0001) plane. The second set is comprised of rectangular loops with b = 1/3 [110] (perpendicular to the coalescence boundary) which originate in the coalescence boundary and extend laterally into the film on the (100). The third set of dislocations threads laterally through the film along the [100] bar axis with 1/3<110>-type Burgers vectors These sets result in a dislocation density of ∼109 cm−2. High resolution X-ray reciprocal space maps indicate wing tilt of ∼0.5º.

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Investigation of Residual Strains of the Second Kind in Plastically Deformed Metallic Materials

MRS Proceedings ◽

10.1557/proc-376-409 ◽

1994 ◽

Vol 376 ◽

Cited By ~ 2

Author(s):

M. Vrána ◽

P. Klimanek ◽

T. Kschidock ◽

P. Lukáš ◽

P. Mikula

Keyword(s):

High Resolution ◽

Neutron Diffraction ◽

Stacking Faults ◽

Metallic Materials ◽

Line Broadening ◽

X Ray Diffraction ◽

X Ray ◽

Neutron Diffractometer ◽

Residual Strains ◽

Good Agreement

ABSTRACTInvestigation of strongly distorted crystal structures caused by dislocations, stacking-faults etc. in both plastically deformed f.c.c. and b.c.c. metallic materials was performed by the analysis of the neutron diffraction line broadening. Measurements were realized by means of the high resolution triple-axis neutron diffractometer equipped by bent Si perfect crystals as monochromator and analyzer at the NPI Řež. The substructure parameters obtained in this manner are in good agreement with the results of X-ray diffraction analysis.

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