scholarly journals The Diffraction Pattern Calculator(DPC) toolkit: a user-friendly approach to unit-cell lattice parameter identification of two-dimensional grazing-incidence wide-angle X-ray scattering data

2014 ◽  
Vol 47 (6) ◽  
pp. 2090-2099 ◽  
Author(s):  
Anna K. Hailey ◽  
Anna M. Hiszpanski ◽  
Detlef-M. Smilgies ◽  
Yueh-Lin Loo
Keyword(s):  
Crystal Structure ◽  
Grazing Incidence ◽  
Unit Cell ◽  
Lattice Parameters ◽  
Scattering Data ◽  
Wide Angle ◽  
Two Dimensional ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

TheDPCtoolkit is a simple-to-use computational tool that helps users identify the unit-cell lattice parameters of a crystal structure that are consistent with a set of two-dimensional grazing-incidence wide-angle X-ray scattering data. The input data requirements are minimal and easy to assemble from data sets collected with any position-sensitive detector, and the user is required to make as few initial assumptions about the crystal structure as possible. By selecting manual or automatic modes of operation, the user can either visually match the positions of the experimental and calculated reflections by individually tuning the unit-cell parameters or have the program perform this process for them. Examples that demonstrate the utility of this program include determining the lattice parameters of a polymorph of a fluorinated contorted hexabenzocoronene in a blind test and refining the lattice parameters of the thin-film phase of 5,11-bis(triethylsilylethynyl)anthradithiophene with the unit-cell dimensions of its bulk crystal structure being the initial inputs.

An instrument for time-resolved and anomalous simultaneous small- and wide-angle X-ray scattering (SWAXS) at NSRRC

2006 ◽  
Vol 39 (6) ◽  
pp. 871-877 ◽  
Author(s):  
Ying-Huang Lai ◽  
Ya-Sen Sun ◽  
U-Ser Jeng ◽  
Jhih-Min Lin ◽  
Tsang-Lang Lin ◽  
...  
Keyword(s):  
Lipid Membrane ◽  
Quantum Wires ◽  
Grazing Incidence ◽  
Anomalous Scattering ◽  
Wide Angle ◽  
Scanning Calorimetry ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

A SWAXS (small- and wide-angle X-ray scattering) instrument was recently installed at the wiggler beamline BL17B3 of the National Synchrotron Radiation Research Center (NSRRC), Taiwan. The instrument, which is designed for studies of static and dynamic nanostructures and correlations between the nano (ormeso) structure (SAXS) and crystalline structure (WAXS), provides a flux of 1010–1011photon s−1at the sample at energies between 5 and 14 keV. With a SAXS area detector and a WAXS linear detector connected to two data acquisition systems operated in master–slave mode, the instrument allows one to perform time-resolved as well as anomalous scattering measurements. Data reduction algorithms have been developed for rapid processing of the large SWAXS data sets collected during time-resolved measurements. The performance of the instrument is illustrated by examples taken from different classes of ongoing projects: (i) time-resolved SAXS/WAXS/differential scanning calorimetry (DSC) with a time resolution of 10 s on a semicrystalline poly(hexamethylene terephthalate) sample, (ii) anomalous SAXS/WAXS measurements on a nanoparticulate PtRu catalyst, and (iii) grazing-incidence SAXS of a monolayer of oriented semiconductor quantum wires, and humidity-controlled ordering of Alamethicin peptides embedded in an oriented lipid membrane.

iA program package for preprocessing of two-dimensional detector data

1995 ◽  
Vol 28 (5) ◽  
pp. 630-632
Author(s):  
M. Lorenzen ◽  
C. Ferrero ◽  
O. Diat ◽  
C. Riekel ◽  
U. Mayerhofer
Keyword(s):  
Data Analysis ◽  
Powder Diffraction ◽  
Program Package ◽  
Background Correction ◽  
Wide Angle ◽  
Two Dimensional ◽  
Detailed Data ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

A set of macros based on CERN's program package PAW has been developed for interactive preprocessing of two-dimensional detector data at ESRF prior to more detailed data analysis. Various types of image operations (averaging, cuts, background correction etc.) are available. The main use of the package is at present in small- and wide-angle X-ray scattering (SAXS and WAXS). The flexibility of the package allows, however, easy adaptation to other areas such as fibre or powder diffraction.

Two-dimensional camera for millisecond range time-resolved small- and wide-angle X-ray scattering

2003 ◽  
Vol 36 (3) ◽  
pp. 809-811 ◽  
Author(s):  
Volker Urban ◽  
Pierre Panine ◽  
Cyril Ponchut ◽  
Peter Boesecke ◽  
Theyencheri Narayanan
Keyword(s):  
Wide Angle ◽  
Two Dimensional ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Scattering ◽  
Millisecond Range ◽  
Ray Scattering

scholarly journals Combining solution wide-angle X-ray scattering and crystallography: determination of molecular envelope and heavy-atom sites

2009 ◽  
Vol 42 (2) ◽  
pp. 259-264 ◽  
Author(s):  
Xinguo Hong ◽  
Quan Hao
Keyword(s):  
Structure Determination ◽  
Heavy Atom ◽  
Unit Cell ◽  
Wide Angle ◽  
X Ray ◽  
X Ray Scattering ◽  
Molecular Envelope ◽  
Waxs Data ◽  
Ray Scattering

Solving the phase problem remains central to crystallographic structure determination. A six-dimensional search method of molecular replacement (FSEARCH) can be used to locate a low-resolution molecular envelope determined from small-angle X-ray scattering (SAXS) within the crystallographic unit cell. This method has now been applied using the higher-resolution envelope provided by combining SAXS and WAXS (wide-angle X-ray scattering) data. The method was tested on horse hemoglobin, using the most probable model selected from a set of a dozen bead models constructed from SAXS/WAXS data using the programGASBORat 5 Å resolution (qmax= 1.25 Å−1) to phase a set of single-crystal diffraction data. It was found that inclusion of WAXS data is essential for correctly locating the molecular envelope in the crystal unit cell, as well as for locating heavy-atom sites. An anomalous difference map was calculated using phases out to 8 Å resolution from the correctly positioned envelope; four distinct peaks at the 3.2σ level were identified, which agree well with the four iron sites of the known structure (Protein Data Bank code 1ns9). In contrast, no peaks could be found close to the iron sites if the molecular envelope was constructed using the data from SAXS alone (qmax= 0.25 Å−1). The initial phases can be used as a starting point for a variety of phase-extension techniques, successful application of which will result in complete phasing of a crystallographic data set and determination of the internal structure of a macromolecule to atomic resolution. It is anticipated that the combination ofFSEARCHand WAXS techniques will facilitate the initial structure determination of proteins and provide a good foundation for further structure refinement.

scholarly journals GIWAXS-SIIRkit: scattering intensity, indexing and refraction calculation toolkit for grazing-incidence wide-angle X-ray scattering of organic materials

2020 ◽  
Vol 53 (4) ◽  
pp. 1108-1129 ◽  
Author(s):  
Victoria Savikhin ◽  
Hans-Georg Steinrück ◽  
Ru-Ze Liang ◽  
Brian A. Collins ◽  
Stefan D. Oosterhout ◽  
...  
Keyword(s):  
Organic Materials ◽  
Grazing Incidence ◽  
Peak Position ◽  
Wide Angle ◽  
Scattering Intensity ◽  
X Ray ◽  
Short Learning Curve ◽  
X Ray Scattering ◽  
Intensity Normalization ◽  
Ray Scattering

Grazing-incidence wide-angle X-ray scattering (GIWAXS) has become an increasingly popular technique for quantitative structural characterization and comparison of thin films. For this purpose, accurate intensity normalization and peak position determination are crucial. At present, few tools exist to estimate the uncertainties of these measurements. Here, a simulation package is introduced called GIWAXS-SIIRkit, where SIIR stands for scattering intensity, indexing and refraction. The package contains several tools that are freely available for download and can be executed in MATLAB. The package includes three functionalities: estimation of the relative scattering intensity and the corresponding uncertainty based on experimental setup and sample dimensions; extraction and indexing of peak positions to approximate the crystal structure of organic materials starting from calibrated GIWAXS patterns; and analysis of the effects of refraction on peak positions. Each tool is based on a graphical user interface and designed to have a short learning curve. A user guide is provided with detailed usage instruction, tips for adding functionality and customization, and exemplary files.

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