Surface Correlation Function Analysis Of High Resolution Scattering Data From Mirrored Surfaces Obtained Using A Triple-Axis X-Ray Diffractometer

1988 ◽  
Author(s):  
Finn E. Christensen ◽  
A. Hornstrup ◽  
Herbert W. Schnopper
Keyword(s):  
Correlation Function ◽  
High Resolution ◽  
Function Analysis ◽  
Scattering Data ◽  
X Ray

Comparison of total scattering data from various sources: the case of a nanometric spinel

2015 ◽  
Vol 30 (S1) ◽  
pp. S65-S69 ◽  
Author(s):  
Giorgia Confalonieri ◽  
Monica Dapiaggi ◽  
Marco Sommariva ◽  
Milen Gateshki ◽  
Andy N. Fitch ◽  
...  
Keyword(s):  
High Resolution ◽  
High Energy ◽  
European Synchrotron Radiation Facility ◽  
Distribution Functions ◽  
Scattering Data ◽  
Data Set ◽  
Total Scattering ◽  
X Ray ◽  
Fair Comparison ◽  
Pair Distribution Functions

Total scattering data of nanocrystalline gahnite (ZnAl2O4, 2–3 nm) have been collected with three of the most commonly used instruments: (i) ID31 high-resolution diffractometer at the European Synchrotron Radiation Facility (ESRF) (Qmax = 22 Å−1); (ii) ID11 high-energy beamline at the ESRF (Qmax = 26.6 Å−1); and (iii) Empyrean laboratory diffractometer by PANalytical with molybdenum anode X-ray tube (Qmax = 17.1 Å−1). Pair distribution functions (PDFs) for each instrument data-set have been obtained, changing some of the parameters, by PDFgetX3 software, with the aim of testing the software in the treatment of different total scattering data. The material under analysis has been chosen for its nanometric (and possibly disordered) nature, to give rise to a challenge for all the diffractometers involved. None of the latter should have a clear advantage. The PDF and F(Q) functions have been visually compared, and then the three PDF sets have been used for refinements by means of PDFgui suite. All the refinements have been made exactly in the same way for the sake of a fair comparison. Small differences could be observed in the experimental PDFs and the derived results, but none of them seemed to be significant.

scholarly journals Operando X-ray scattering study of thermoelectric β-Zn4Sb3

IUCrJ ◽  
2020 ◽  
Vol 7 (1) ◽  
pp. 100-104
Author(s):  
Lasse Rabøl Jørgensen ◽  
Christian Moeslund Zeuthen ◽  
Kasper Andersen Borup ◽  
Martin Roelsgaard ◽  
Nils Lau Nyborg Broge ◽  
...  
Keyword(s):  
Structural Integrity ◽  
Function Analysis ◽  
Electrical Current ◽  
Operational Reliability ◽  
Operating Conditions ◽  
Scattering Data ◽  
X Ray ◽  
X Ray Scattering ◽  
Sample Decomposition ◽  
Ray Scattering

The application of thermoelectrics for energy harvesting depends strongly on operational reliability and it is therefore desirable to investigate the structural integrity of materials under operating conditions. We have developed an operando setup capable of simultaneously measuring X-ray scattering data and electrical resistance on pellets subjected to electrical current. Here, operando investigations of β-Zn4Sb3 are reported at current densities of 0.5, 1.14 and 2.3 A mm−2. At 0.5 A mm−2 no sample decomposition is observed, but Rietveld refinements reveal increased zinc occupancy from the anode to the cathode demonstrating zinc migration under applied current. At 1.14 A mm−2 β-Zn4Sb3 decomposes into ZnSb, but pair distribution function analysis shows that Zn2Sb2 units are preserved during the decomposition. This identifies the mobile zinc in β-Zn4Sb3 as the linkers between the Zn2Sb2 units. At 2.3 A mm−2 severe Joule heating triggers transition into the γ-Zn4Sb3 phase, which eventually decomposes into ZnSb, demonstrating Zn ion mobility also in γ-Zn4Sb3 under electrical current.

Catalytic Fe-Oxo Clusters Stabilized on the MOF-808 Metal Organicframework for the Degradation of Water Pollutants

2020 ◽  
Author(s):  
Celia Castillo-Blas ◽  
Ignacio Romero-Muñiz ◽  
Andreas Mavrandonakis ◽  
Laura Simonelli ◽  
Ana Eva Platero Prats
Keyword(s):  
Function Analysis ◽  
Computational Modelling ◽  
Scattering Data ◽  
X Ray ◽  
X Ray Scattering ◽  
Redox Active ◽  
Nanoporous Metal ◽  
Metal Organic ◽  
X Ray Absorption ◽  
Powerful Strategy

<p>Stabilizing catalytic iron-oxo-clusters within nanoporous metal-organic frameworks (MOF) is a powerful strategy to prepare new active materials for the degradation of toxic chemicals, such as bisphenol A. Herein, we combine pair distribution function analysis of total X-ray scattering data and X-ray absorption spectroscopy, with computational modelling to understand the local structural nature of added redox-active iron-oxo clusters bridging neighbouring zirconia-nodes within MOF-808.</p>

scholarly journals Local structural studies on Co doped ZnS nanowires by synchrotron X-ray atomic pair distribution function and micro-Raman shift

RSC Advances ◽  
2017 ◽  
Vol 7 (59) ◽  
pp. 37402-37411 ◽  
Author(s):  
U. P. Gawai ◽  
B. N. Dole
Keyword(s):  
Distribution Function ◽  
Pair Distribution Function ◽  
Function Analysis ◽  
Scattering Data ◽  
Raman Shift ◽  
X Ray ◽  
Atomic Structures ◽  
Atomic Pair Distribution Function ◽  
X Ray Scattering ◽  
Atomic Pair

The atomic structures of nanowires were studied by X-ray atomic pair distribution function analysis and total synchrotron X-ray scattering data. A PDF method was used to describe a wurtzite and zinc-blended mixed phase model.

scholarly journals Catalytic Fe-Oxo Clusters Stabilized on the MOF-808 Metal Organicframework for the Degradation of Water Pollutants

2020 ◽  
Author(s):  
Celia Castillo-Blas ◽  
Ignacio Romero-Muñiz ◽  
Andreas Mavrandonakis ◽  
Laura Simonelli ◽  
Ana Eva Platero Prats
Keyword(s):  
Function Analysis ◽  
Computational Modelling ◽  
Scattering Data ◽  
X Ray ◽  
X Ray Scattering ◽  
Redox Active ◽  
Nanoporous Metal ◽  
Metal Organic ◽  
X Ray Absorption ◽  
Powerful Strategy

<p>Stabilizing catalytic iron-oxo-clusters within nanoporous metal-organic frameworks (MOF) is a powerful strategy to prepare new active materials for the degradation of toxic chemicals, such as bisphenol A. Herein, we combine pair distribution function analysis of total X-ray scattering data and X-ray absorption spectroscopy, with computational modelling to understand the local structural nature of added redox-active iron-oxo clusters bridging neighbouring zirconia-nodes within MOF-808.</p>

scholarly journals D+: software for high-resolution hierarchical modeling of solution X-ray scattering from complex structures

2019 ◽  
Vol 52 (1) ◽  
pp. 219-242 ◽  
Author(s):  
Avi Ginsburg ◽  
Tal Ben-Nun ◽  
Roi Asor ◽  
Asaf Shemesh ◽  
Lea Fink ◽  
...  
Keyword(s):  
High Resolution ◽  
Hybrid Method ◽  
Scattering Amplitude ◽  
Protein Data Bank File ◽  
Scattering Data ◽  
Complex Structures ◽  
X Ray ◽  
Atomic Models ◽  
X Ray Scattering ◽  
Ray Scattering

This paper presents the computer program D+ (https://scholars.huji.ac.il/uriraviv/book/d-0), where the reciprocal-grid (RG) algorithm is implemented. D+ efficiently computes, at high-resolution, the X-ray scattering curves from complex structures that are isotropically distributed in random orientations in solution. Structures are defined in hierarchical trees in which subunits can be represented by geometric or atomic models. Repeating subunits can be docked into their assembly symmetries, describing their locations and orientations in space. The scattering amplitude of the entire structure can be calculated by computing the amplitudes of the basic subunits on 3D reciprocal-space grids, moving up in the hierarchy, calculating the RGs of the larger structures, and repeating this process for all the leaves and nodes of the tree. For very large structures (containing over 100 protein subunits), a hybrid method can be used to avoid numerical artifacts. In the hybrid method, only grids of smaller subunits are summed and used as subunits in a direct computation of the scattering amplitude. D+ can accurately analyze both small- and wide-angle solution X-ray scattering data. This article describes how D+ applies the RG algorithm, accounts for rotations and translations of subunits, processes atomic models, accounts for the contribution of the solvent as well as the solvation layer of complex structures in a scalable manner, writes and accesses RGs, interpolates between grid points, computes numerical integrals, enables the use of scripts to define complicated structures, applies fitting algorithms, accounts for several coexisting uncorrelated populations, and accelerates computations using GPUs. D+ may also account for different X-ray energies to analyze anomalous solution X-ray scattering data. An accessory tool that can identify repeating subunits in a Protein Data Bank file of a complex structure is provided. The tool can compute the orientation and translation of repeating subunits needed for exploiting the advantages of the RG algorithm in D+. A Python wrapper (https://scholars.huji.ac.il/uriraviv/book/python-api) is also available, enabling more advanced computations and integration of D+ with other computational tools. Finally, a large number of tests are presented. The results of D+ are compared with those of other programs when possible, and the use of D+ to analyze solution scattering data from dynamic microtubule structures with different protofilament number is demonstrated. D+ and its source code are freely available for academic users and developers (https://bitbucket.org/uriraviv/public-dplus/src/master/).

scholarly journals Quantitative Analysis of Semicrystalline Blends SAXS Data: Theoretical Modeling versus Linear Correlation Function

2010 ◽  
Vol 2010 ◽  
pp. 1-6 ◽  
Author(s):  
Mohamed Fatnassi ◽  
Fadhel Ben Cheikh Larbi ◽  
Jean Louis Halary
Keyword(s):  
Correlation Function ◽  
Vinylidene Fluoride ◽  
Theoretical Modeling ◽  
Scattering Data ◽  
Saxs Data ◽  
One Dimensional ◽  
X Ray ◽  
X Ray Scattering ◽  
Poly Vinylidene Fluoride ◽  
Ray Scattering

This paper compares the results yielded by two methods of small-angle X-ray scattering data analysis for semicrystalline polymer blends. The first method is based on the use of a theoretical modeling for isotropic samples and a subsequent curve fitting. The second one is a more familiar method, based on the calculation of the linear one-dimensional correlation function. The experimental material considered for this purpose deals with a series of semi-crystalline blends of poly(vinylidene fluoride) and poly(methyl methacrylate), with a PVDF content covering the range 50 wt%–100 wt%. The results obtained by both calculation methods are systematically confronted to the crystallinity degrees deduced from wide angle X-ray scattering patterns.

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