Thermal expansion of a glassy alloy studied using a real-space pair distribution function

X-ray pair distribution function analysis is used with first-principles molecular dynamics simulations to study the co-operative H2O binding, structural dynamics and host-guest interactions in the channel hydrate of diflunisal.

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There's no place like real-space: elucidating size-dependent atomic structure of nanomaterials using pair distribution function analysis

Nanoscale Advances ◽

10.1039/d0na00120a ◽

2020 ◽

Vol 2 (6) ◽

pp. 2234-2254 ◽

Cited By ~ 6

Author(s):

Troels Lindahl Christiansen ◽

Susan R. Cooper ◽

Kirsten M. Ø. Jensen

Keyword(s):

Distribution Function ◽

Atomic Structure ◽

Pair Distribution Function ◽

Function Analysis ◽

Real Space ◽

Size Dependent ◽

Structure Of Nanomaterials

We review the use of pair distribution function analysis for characterization of atomic structure in nanomaterials.

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Precise implications for real-space pair distribution function modeling of effects intrinsic to modern time-of-flight neutron diffractometers

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273318003224 ◽

2018 ◽

Vol 74 (4) ◽

pp. 293-307 ◽

Cited By ~ 15

Author(s):

Daniel Olds ◽

Claire N. Saunders ◽

Megan Peters ◽

Thomas Proffen ◽

Joerg Neuefeind ◽

...

Keyword(s):

Distribution Function ◽

Pair Distribution Function ◽

Amorphous Materials ◽

Best Practice ◽

Time Of Flight ◽

Real Space ◽

Mitigation Strategies ◽

Total Scattering ◽

Conventional Analysis ◽

Pdf Analysis

Total scattering and pair distribution function (PDF) methods allow for detailed study of local atomic order and disorder, including materials for which Rietveld refinements are not traditionally possible (amorphous materials, liquids, glasses and nanoparticles). With the advent of modern neutron time-of-flight (TOF) instrumentation, total scattering studies are capable of producing PDFs with ranges upwards of 100–200 Å, covering the correlation length scales of interest for many materials under study. Despite this, the refinement and subsequent analysis of data are often limited by confounding factors that are not rigorously accounted for in conventional analysis programs. While many of these artifacts are known and recognized by experts in the field, their effects and any associated mitigation strategies largely exist as passed-down `tribal' knowledge in the community, and have not been concisely demonstrated and compared in a unified presentation. This article aims to explicitly demonstrate, through reviews of previous literature, simulated analysis and real-world case studies, the effects of resolution, binning, bounds, peak shape, peak asymmetry, inconsistent conversion of TOF to d spacing and merging of multiple banks in neutron TOF data as they directly relate to real-space PDF analysis. Suggestions for best practice in analysis of data from modern neutron TOF total scattering instruments when using conventional analysis programs are made, as well as recommendations for improved analysis methods and future instrument design.

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A simple correction for the parallax effect in X-ray pair distribution function measurements

Journal of Applied Crystallography ◽

10.1107/s1600576719011580 ◽

2019 ◽

Vol 52 (5) ◽

pp. 1072-1076 ◽

Cited By ~ 1

Author(s):

Frederick Marlton ◽

Oleh Ivashko ◽

Martin v. Zimmerman ◽

Olof Gutowski ◽

Ann-Christin Dippel ◽

...

Keyword(s):

Distribution Function ◽

Rietveld Refinement ◽

Powder Diffraction ◽

Pair Distribution Function ◽

Reference Data ◽

Real Space ◽

X Ray ◽

Local Structures ◽

Pdf Analysis ◽

Complex Nanostructures

Total scattering and pair distribution function (PDF) analysis has created new insights that traditional powder diffraction methods have been unable to achieve in understanding the local structures of materials exhibiting disorder or complex nanostructures. Care must be taken in such analyses as subtle and discrete features in the PDF can easily be artefacts generated in the measurement process, which can result in unphysical models and interpretation. The focus of this study is an artefact called the parallax effect, which can occur in area detectors with thick detection layers during the collection of X-ray PDF data. This effect results in high-Q peak offsets, which subsequently cause an r-dependent shift in the PDF peak positions in real space. Such effects should be accounted for if a truly accurate model is to be achieved, and a simple correction that can be conducted via a Rietveld refinement against the reference data is proposed.

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Reciprocal-space instrumental effects on the real-space neutron atomic pair distribution function

Journal of Applied Crystallography ◽

10.1107/s0021889803026670 ◽

2004 ◽

Vol 37 (1) ◽

pp. 110-116 ◽

Cited By ~ 70

Author(s):

Xiangyun Qiu ◽

Emil S. Božin ◽

Pavol Juhas ◽

Thomas Proffen ◽

Simon J. L. Billinge

Keyword(s):

Distribution Function ◽

Pair Distribution Function ◽

Real Space ◽

Measurement Range ◽

Instrumental Effects ◽

The Real ◽

Atomic Pair Distribution Function ◽

Specific Effects ◽

Atomic Pair ◽

Asymmetric Shape

An atomic pair distribution function (PDF) neutron powder diffraction round-robin experiment was performed on six diffractometers at three spallation sources. Instrument-specific effects on the real-space PDF were investigated, such as finite measurement range, the instrument resolution and the asymmetric shape of diffraction peaks. Two illustrative samples, a perfectly long-range-ordered element, Pb, and a locally strained alloy ZnSe0.5Te0.5, were measured at low temperatures. Various aspects of the PDF were explored, either qualitatively by direct comparison or quantitativelyviastructural modelling. Future implementation of modelling codes incorporating some of these instrumental effects are also discussed.

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The Polymorphs of the Na+ Ion Conductor Na3PS4 from the Perspective of Variable Temperature Diffraction and Spectroscopy

10.26434/chemrxiv.13567454.v1 ◽

2021 ◽

Author(s):

Theodosios Famprikis ◽

Houssny Bouyanfif ◽

Pieremanuele Canepa ◽

James Dawson ◽

Mohamed Zbiri ◽

...

Keyword(s):

Phase Transition ◽

Distribution Function ◽

Order Phase Transition ◽

Pair Distribution Function ◽

Function Analysis ◽

Variable Temperature ◽

Real Space ◽

Bragg Diffraction ◽

Effect Of Temperature ◽

Ion Conductor

Solid electrolytes are crucial for next generation solid state batteries and Na3PS4 is one of the most promising Na+ conductors for such applications. In this contribution, we present a detailed investigation of the evolution in structure and dynamics of Na3PS4 under the effect of temperature in the range 30 < T < 600 °C through combined experimental-computational analysis. Although x ray Bragg diffraction experiments indicate a second order phase transition from the tetragonal ground state (α, P-421c) to the cubic polymorph (β, I-43m), pair distribution function analysis in real space and Raman spectroscopy indicate remnants of tetragonal character in the range 250 < T < 500 °C which we attribute to dynamic local tetragonal distortions. The first order phase transition to the mesophasic high temperature polymorph (γ, Fddd) is associated with a sharp volume increase and the onset of liquid like diffusive dynamics for sodium-cations (translative) and thiophosphate-polyanions (rotational) evident by inelastic neutron- and Raman- spectroscopies, as well as pair-distribution function and molecular dynamics. These results shed light on the rich polymorphism in Na3PS4 and are relevant for a host of high performance materials deriving from the Na3PS4 structural archetype.

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Real-Space X-Ray Pair Distribution Function Analysis and Molecular-Dynamics Modelling of Diflunisal Channel Hydrates

10.26434/chemrxiv.12837524.v1 ◽

2020 ◽

Author(s):

Anuradha Pallipurath ◽

Francesco Civati ◽

Jonathan Skelton ◽

Dean Keeble ◽

Clare Crowley ◽

...

Keyword(s):

Molecular Dynamics ◽

Distribution Function ◽

Structural Dynamics ◽

First Principles ◽

Pair Distribution Function ◽

Function Analysis ◽

Real Space ◽

X Ray ◽

Dynamics Modelling ◽

Dynamics Simulations

X-ray pair distribution function analysis is used with first-principles molecular dynamics simulations to study the co-operative H2O binding, structural dynamics and host-guest interactions in the channel hydrate of diflunisal.

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Reprobing the mechanism of negative thermal expansion in siliceous faujasite

RSC Advances ◽

10.1039/c5ra23827g ◽

2016 ◽

Vol 6 (24) ◽

pp. 19903-19909 ◽

Cited By ~ 7

Author(s):

M. P. Attfield ◽

M. Feygenson ◽

J. C. Neuefeind ◽

T. E. Proffen ◽

T. C. A. Lucas ◽

...

Keyword(s):

Thermal Expansion ◽

Distribution Function ◽

Neutron Scattering ◽

Rietveld Refinement ◽

Pair Distribution Function ◽

Function Analysis ◽

Negative Thermal Expansion ◽

Scattering Data ◽

Total Neutron ◽

Expansion Mechanism

Combined Rietveld refinement and pair distribution function analysis of total neutron scattering data unveils the finer details of the negative thermal expansion mechanism of siliceous faujasite.

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