Full-pattern analysis of two-dimensional small-angle scattering data from oriented polymers using elliptical coordinates

This article presents a new program that allows highly automatized analyses of series of, especially, anisotropic two-dimensional neutron and X-ray small-angle scattering data as well as one-dimensional data series. The main aim of this work was to reduce the effort of the analysis of complex scattering systems, which remains an essential burden in the evaluation process of complex systems. The program is built in a modular manner to support a stepwise analysis of small-angle scattering data. For example, from a two-dimensional data series, features such as anisotropy or changes of the preferred scattering direction or intensities along the radial or azimuthal directions as well as along the series axis (e.g. time axis) can quickly be extracted. Different anisotropy measurement methods are available, which are described herein. In a second step, physical scattering models can be fitted to the extracted data. More complex models can be easily added. The fitting procedure can be applied with nearly every possible constraint and works automatically on whole scattering data series. Furthermore, simultaneous fitting can be used to analyze coupled series, and parallel working methods are implemented to speed up the code execution. Finally, results can be easily visualized. The name of the program isSASET, which is an acronym standing for small-angle scattering evaluation tool.SASETis based on MATLAB.

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Interpretation of two-dimensional real-space functions obtained from small-angle scattering data of oriented microstructures

Journal of Applied Crystallography ◽

10.1107/s1600576714024972 ◽

2015 ◽

Vol 48 (1) ◽

pp. 44-51 ◽

Cited By ~ 8

Author(s):

Gerhard Fritz-Popovski

Keyword(s):

Small Angle ◽

Fourier Transformation ◽

Real Space ◽

Small Angle Scattering ◽

Scattering Data ◽

Two Dimensional ◽

Spruce Wood ◽

Angle Scattering ◽

Nanostructured Silica ◽

Internal Architecture

The new two-dimensional indirect Fourier transformation converts small-angle scattering patterns obtained by means of area detectors into two-dimensional real-space functions. These functions contain identical information to the scattering patterns, but many parameters related to the microstructure can be obtained directly from them. The size and shape of the microstructures are mainly reflected in the contours of the real-space functions. Their height can be used to get information on the internal architecture of the microstructures. The principles are demonstrated on nanostructured silica biotemplated by spruce wood.

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Two-dimensional indirect Fourier transformation for evaluation of small-angle scattering data of oriented samples

Journal of Applied Crystallography ◽

10.1107/s002188981302150x ◽

2013 ◽

Vol 46 (5) ◽

pp. 1447-1454 ◽

Cited By ~ 12

Author(s):

Gerhard Fritz-Popovski

Keyword(s):

Small Angle ◽

Fourier Transformation ◽

Real Space ◽

Small Angle Scattering ◽

Basis Functions ◽

Scattering Data ◽

Normal Wood ◽

Two Dimensional ◽

Model Free ◽

Angle Scattering

An extension of the indirect Fourier transformation method for two-dimensional small-angle scattering patterns is presented. This allows for a model-free investigation of real-space functions of oriented structures. The real-space function is built from two-dimensional basis functions. The Fourier transformed basis functions are approximated to the scattering pattern. The solution to this problem in reciprocal space can be used to compute the corresponding real-space functions. These real-space functions contain information on size, shape, internal structure and orientation of the structures studied. Information on structures that are oriented in different distinct directions can be partly separated. The applicability of the technique is demonstrated on simulated data of oriented cuboids and on two experimental data sets based on the nanostructure of spruce normal wood.

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2017 publication guidelines for structural modelling of small-angle scattering data from biomolecules in solution: an update

Acta Crystallographica Section D Structural Biology ◽

10.1107/s2059798317011597 ◽

2017 ◽

Vol 73 (9) ◽

pp. 710-728 ◽

Cited By ~ 107

Author(s):

Jill Trewhella ◽

Anthony P. Duff ◽

Dominique Durand ◽

Frank Gabel ◽

J. Mitchell Guss ◽

...

Keyword(s):

Small Angle ◽

Task Force ◽

Data Bank ◽

Small Angle Scattering ◽

Scattering Data ◽

Quality Data ◽

Angle Scattering ◽

Publication Guidelines ◽

Guidelines And Recommendations

In 2012, preliminary guidelines were published addressing sample quality, data acquisition and reduction, presentation of scattering data and validation, and modelling for biomolecular small-angle scattering (SAS) experiments. Biomolecular SAS has since continued to grow and authors have increasingly adopted the preliminary guidelines. In parallel, integrative/hybrid determination of biomolecular structures is a rapidly growing field that is expanding the scope of structural biology. For SAS to contribute maximally to this field, it is essential to ensure open access to the information required for evaluation of the quality of SAS samples and data, as well as the validity of SAS-based structural models. To this end, the preliminary guidelines for data presentation in a publication are reviewed and updated, and the deposition of data and associated models in a public archive is recommended. These guidelines and recommendations have been prepared in consultation with the members of the International Union of Crystallography (IUCr) Small-Angle Scattering and Journals Commissions, the Worldwide Protein Data Bank (wwPDB) Small-Angle Scattering Validation Task Force and additional experts in the field.

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A new method for the evaluation of small-angle scattering data

Journal of Applied Crystallography ◽

10.1107/s0021889877013879 ◽

1977 ◽

Vol 10 (5) ◽

pp. 415-421 ◽

Cited By ~ 833

Author(s):

O. Glatter

Keyword(s):

Small Angle ◽

Small Angle Scattering ◽

New Method ◽

Scattering Data ◽

Angle Scattering

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Determination of size distribution from small-angle scattering data for systems with effective hard-sphere interactions

Journal of Applied Crystallography ◽

10.1107/s0021889893013810 ◽

1994 ◽

Vol 27 (4) ◽

pp. 595-608 ◽

Cited By ~ 284

Author(s):

J. S. Pedersen

Keyword(s):

Size Distribution ◽

Small Angle ◽

Hard Sphere ◽

Small Angle Scattering ◽

Scattering Data ◽

Angle Scattering

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SLADS: a parallel code for direct simulations of scattering of large anisotropic dense nanoparticle systems

Journal of Applied Crystallography ◽

10.1107/s1600576717004162 ◽

2017 ◽

Vol 50 (3) ◽

pp. 951-958 ◽

Cited By ~ 6

Author(s):

Sen Chen ◽

Juncheng E ◽

Sheng-Nian Luo

Keyword(s):

Analytical Solutions ◽

Small Angle ◽

Real Space ◽

Small Angle Scattering ◽

Two Dimensional ◽

X Ray ◽

X Ray Scattering ◽

Angle Scattering ◽

Parallel Code ◽

Diffraction Patterns

SLADS(http://www.pims.ac.cn/Resources.html), a parallel code for direct simulations of X-ray scattering of large anisotropic dense nanoparticle systems of arbitrary species and atomic configurations, is presented. Particles can be of arbitrary shapes and dispersities, and interactions between particles are considered. Parallelization is achieved in real space for the sake of memory limitation. The system sizes attempted are up to one billion atoms, and particle concentrations in dense systems up to 0.36. Anisotropy is explored in terms of superlattices. One- and two-dimensional small-angle scattering or diffraction patterns are obtained.SLADSis validated self-consistently or against cases with analytical solutions.

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