Unlocking the structure of mixed amorphous-crystalline ceramic oxide films synthesized under low temperature electromagnetic excitation

2017 ◽  
Vol 5 (35) ◽  
pp. 18434-18441 ◽  
Author(s):  
Nathan Nakamura ◽  
Maxwell W. Terban ◽  
Simon J. L. Billinge ◽  
B. Reeja-Jayan
Keyword(s):  
Distribution Function ◽  
Low Temperature ◽  
Electromagnetic Fields ◽  
Atomic Structure ◽  
Pair Distribution Function ◽  
Electromagnetic Excitation ◽  
X Ray ◽  
Ceramic Oxide ◽  
Pdf Analysis ◽  
Crystalline Ceramic

The effect of electromagnetic fields on nanoscale atomic structure was determined using synchrotron X-ray pair distribution function (PDF) analysis.

scholarly journals Structural Analysis of Ligand Protected Smaller Metallic Nanocrystals by Atomic Pair Distribution Function Under Precession Electron Diffraction

2019 ◽  
Author(s):  
M. Mozammel Hoque ◽  
Sandra Vergara ◽  
Partha P. Das ◽  
Daniel Ugarte ◽  
Ulises Santiago ◽  
...  
Keyword(s):  
Distribution Function ◽  
Electron Diffraction ◽  
Pair Distribution Function ◽  
Electron Diffraction Data ◽  
Face Centered Cubic ◽  
X Ray ◽  
Atomic Pair Distribution Function ◽  
Atomic Pair ◽  
Pdf Analysis ◽  
Precession Electron Diffraction

Atomic pair distribution function (PDF) analysis has been widely used to investigate nanocrystalline and structurally disordered materials. Experimental PDFs retrieved from electron diffraction (ePDF) in transmission electron microscopy (TEM) represent an attractive alternative to traditional PDF obtained from synchrotron X-ray sources, when employed on minute samples. Nonetheless, the inelastic scattering produced by the large dynamical effects of electron diffraction may obscure the interpretation of ePDF. In the present work, precession electron diffraction (PED-TEM) has been employed to obtain the ePDF of two different sub-monolayer samples ––lipoic acid protected (~ 4.5 nm) and hexanethiolated(~ 4.2 nm, ~ 400-kDa core mass) gold nanoparticles­­––randomly oriented and measured at both liquid-nitrogen and room temperatures, with high dynamic-range detection of a CMOS camera. The electron diffraction data were processed to obtain ePDFs which were subsequently compared with PDF of different ideal structure-models. The results demonstrate that the PED-ePDF data is sensitive to different crystalline structures such as monocrystalline (truncated octahedra) versus multiply-twinned (decahedra, icosahedra) structuresof the face-centered cubic gold lattice. The results indicate that PED reduces the residual from 46% to 29%; in addition, the combination of PED and low temperature further reduced the residual to 23%, which is comparable to X-ray PDF analysis. Furthermore, the inclusion of PED resulted in a better estimation of the coordination number from ePDF. To the best of our knowledge, the precessed electron-beam technique (PED) has not been previously applied to nanoparticles for analysis by the ePDF method.

scholarly journals Drying-induced atomic structural rearrangements in sodium-based calcium-alumino-silicate-hydrate gel and the mitigating effects of ZrO2 nanoparticles

2018 ◽  
Vol 20 (13) ◽  
pp. 8593-8606 ◽  
Author(s):  
Kengran Yang ◽  
V. Ongun Özçelik ◽  
Nishant Garg ◽  
Kai Gong ◽  
Claire E. White
Keyword(s):  
Distribution Function ◽  
Atomic Structure ◽  
Pair Distribution Function ◽  
Function Analysis ◽  
Zro2 Nanoparticles ◽  
Structural Rearrangements ◽  
X Ray ◽  
Alumino Silicate ◽  
Activated Slag

Drying-induced nanoscopic alterations to the local atomic structure of silicate-activated slag and the mitigated effects of nano-ZrO2 are elucidated using in situ X-ray pair distribution function analysis.

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

2019 ◽  
Vol 52 (5) ◽  
pp. 1072-1076 ◽  
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.

scholarly journals Total-scattering pair-distribution function analysis of zinc from high-energy synchrotron data

2019 ◽  
Vol 33 (33) ◽  
pp. 1950410 ◽  
Author(s):  
Ahmad S. Masadeh ◽  
Moneeb T. M. Shatnawi ◽  
Ghosoun Adawi ◽  
Yang Ren
Keyword(s):  
Crystal Structure ◽  
Distribution Function ◽  
Pair Distribution Function ◽  
Function Analysis ◽  
High Energy ◽  
Ambient Conditions ◽  
Total Scattering ◽  
X Ray ◽  
Zinc Metal ◽  
Pdf Analysis

The crystal structure of zinc metal deviates from the ideal hexagonal close packing structure by a significantly increased axial ratio (c/a). The local atomic structure of zinc metal is investigated using the total scattering atomic pair distribution function (PDF) analysis based on X-ray powder diffraction data collected at ambient conditions. The X-ray total scattering PDF analysis confirms that the crystal structure of zinc can be described in terms of wurtzite structure, but with an anomalously atomic displacement parameters [Formula: see text], indicating a significant displacement disorder along the [Formula: see text]-axis. For the long [Formula: see text]-range PDF refinements, the thermal motion of zinc shows a notable anisotropy as expressed by the ratio [Formula: see text]/[Formula: see text] of 2.5 at ambient conditions. This average distortion level along the [Formula: see text]-axis, was not reflected locally for the features below 5.0 Å as it fits the high [Formula: see text] region. Based on PDF refinements over different [Formula: see text]-ranges, we measure an interesting increase of the [Formula: see text] value with decreasing the [Formula: see text]-range of the refinement. This suggests that the local structure features in zinc metal differ from the average structure ones.

scholarly journals PDF Analysis on a Laboratory System: Adapting the Experiment to the Material

2014 ◽  
Vol 70 (a1) ◽  
pp. C870-C870
Author(s):  
Céleste Reiss ◽  
Milen Gateshki ◽  
Marco Sommariva
Keyword(s):  
Distribution Function ◽  
Pair Distribution Function ◽  
Amorphous Materials ◽  
Nearest Neighbors ◽  
High Energy ◽  
Experimental Point ◽  
Laboratory System ◽  
Crystalline Materials ◽  
X Ray ◽  
Pdf Analysis

The increased interest in recent years regarding the properties and applications of nanomaterials has also created the need to characterize the structures of these materials. However, due to the lack of long-range atomic ordering, the structures of nanostructured and amorphous materials are not accessible by conventional diffraction methods used to study crystalline materials. One of the most promising techniques to study nanostructures using X-ray diffraction is by using the total scattering (Bragg peaks and diffuse scattering) from the samples and the pair distribution function (PDF) analysis. The pair distribution function provides the probability of finding atoms separated by a certain distance. This function is not direction-dependent; it only looks at the absolute value of the distance between the nearest neighbors, the next nearest neighbors and so on. The method can therefore also be used to analyze non-crystalline materials. From experimental point of view a typical PDF analysis requires the use of intense high-energy X-ray radiation (E ≥ 20 KeV) and a wide 2θ range. After the initial feasibility studies regarding the use of standard laboratory diffraction equipment for PDF analysis [1-3] this application has been further developed to achieve improved data quality and to extend the range of materials, environmental conditions and geometrical configurations that can be used for PDF experiments. Studies performed on different nanocrystalline and amorphous materials of scientific and technological interest, including organic substances, oxides, metallic alloys, etc. have demonstrated that PDF analysis with a laboratory diffractometer can be a valuable tool for structural characterization of nanomaterials. This contribution presents several examples of laboratory PDF studies, in which the experimental conditions have been successfully adapted to match the specific requirements of materials under investigation.

scholarly journals New insights into the application of pair distribution function studies to biogenic and synthetic hydroxyapatites

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Emily L. Arnold ◽  
Dean S. Keeble ◽  
Charlene Greenwood ◽  
Keith D. Rogers
Keyword(s):  
Distribution Function ◽  
Pair Distribution Function ◽  
Principal Component ◽  
Peak Position ◽  
Carbonate Content ◽  
X Ray ◽  
X Ray Scattering ◽  
Carbonate Substitution ◽  
Wide Range ◽  
Pdf Analysis

Abstract Biogenic and synthetic hydroxyapatites are confounding materials whose properties remain uncertain, even after years of study. Pair distribution function (PDF) analysis was applied to hydroxyapatites in the 1970’s and 1980’s, but this area of research has not taken full advantage of the relatively recent advances in synchrotron facilities. Here, synchrotron X-ray PDF analysis is compared to techniques commonly used to characterise hydroxyapatite (such as wide angle X-ray scattering, Fourier-transform infrared spectroscopy and thermogravimetric analysis) for a range of biogenic and synthetic hydroxyapatites with a wide range of carbonate substitution. Contributions to the pair distribution function from collagen, carbonate and finite crystallite size were examined through principal component analysis and comparison of PDFs. Noticeable contributions from collagen were observed in biogenic PDFs when compared to synthetic PDFs (namely r < 15 Å), consistent with simulated PDFs of collagen structures. Additionally, changes in local structure were observed for PDFs of synthetic hydroxyapatites with differing carbonate content, notably in features near 4 Å, 8 Å and 19 Å. Regression models were generated to predict carbonate substitution from peak position within the PDFs.

PDF analysis of ferrihydrite and the violation of Pauling's Principia

Clay Minerals ◽  
2010 ◽  
Vol 45 (2) ◽  
pp. 225-228 ◽  
Author(s):  
A. Manceau
Keyword(s):  
Distribution Function ◽  
Neutron Diffraction ◽  
Regression Models ◽  
Pair Distribution Function ◽  
Structural Models ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ferric Oxyhydroxide ◽  
Pdf Analysis ◽  
Crystal Electron

AbstractThe risk of overfitting pair distribution function (PDF) data for highly defective material (Farrow et al., 2007) is illuminated with the example of the nanocrystalline hydrous ferric oxyhydroxide, ferrihydrite. Two structural models have been published by Michel et al. (2007, 2010) using this method, both of which contradict the standard ‘ferrihydrits’ model established by X-ray diffraction (Drits et al., 1993), and confirmed by single-crystal electron nanodiffraction (Janney et al., 2001) and neutron diffraction (Jansen et al., 2002). Although PDF data are reproduced equally well with the two regression models, neither model is realistic: the first (fhyd6) violates Pauling's 2nd rule, and the second (ferrifh), Pauling's 3rd rule.

A study on the synthesis, pair distribution function and diverse properties of cobalt doped ZnS nanowires

CrystEngComm ◽  
2016 ◽  
Vol 18 (8) ◽  
pp. 1439-1445 ◽  
Author(s):  
U. P. Gawai ◽  
H. A. Khawal ◽  
T. Shripathi ◽  
B. N. Dole
Keyword(s):  
Distribution Function ◽  
Band Gap ◽  
Atomic Structure ◽  
Energy Band ◽  
Interatomic Distance ◽  
Pair Distribution Function ◽  
Hexagonal Wurtzite Structure ◽  
Energy Band Gap ◽  
Pdf Analysis ◽  
Co Doped

The fundamental atomic structure of pure and Co doped ZnS nanowires has been studied using pair distribution function (PDF) analysis. It was confirmed that samples have hexagonal (wurtzite) structure. The interatomic distance was calculated using PDF analysis. It was observed that the energy band gap decreases as Co content increases.

scholarly journals Surfactant-free syntheses and pair distribution function analysis of osmium nanoparticles

2021 ◽  
Author(s):  
Mikkel Juelsholt ◽  
Jonathan Quinson ◽  
Emil Kjær ◽  
Baiyu Wang ◽  
Rebecca Pittkowski ◽  
...  
Keyword(s):  
Distribution Function ◽  
Pair Distribution Function ◽  
Large Scale ◽  
Function Analysis ◽  
Scale Production ◽  
Synthetic Process ◽  
X Ray ◽  
Large Scale Production ◽  
Pdf Analysis ◽  
Alkaline Conditions

A surfactant-free synthesis of precious metal nanoparticles performed in low boiling point solvents and in alkaline conditions has been reported recently. This strategy presents several advantages over alternative colloidal syntheses. The resulting nanoparticles are readily relevant for applications like catalysis and the synthetic process is compatible with large scale production. Alkaline mono-alcohols are here investigated as solvent and reducing agents to obtain colloidal Os nanoparticles by this low temperature (< 100 °C) surfactant-free synthesis. The effect of precursor (OsCl3 or H2OsCl6), precursor concentration (up to 100 mM), solvent (methanol or ethanol), presence or absence of base (NaOH) and addition of water (0 to 100 v.%) on the resulting nanomaterials is discussed. It is fond that no base is required to obtain Os nanoparticles as opposed to the case of Pt NPs for instance. The robustness of the synthesis for concentration of precursor up to 100 mM allows to perform X-ray total scattering with pair distribution function (PDF) analysis that shows that the 1-2 nm hcp NPs forms from chain-like [OsOxCly]-complexes.

scholarly journals Electrochemical reactions in fluoride-ion batteries: mechanistic insights from pair distribution function analysis

2017 ◽  
Vol 5 (30) ◽  
pp. 15700-15705 ◽  
Author(s):  
Antonin Grenier ◽  
Ana-Gabriela Porras-Gutierrez ◽  
Henri Groult ◽  
Kevin A. Beyer ◽  
Olaf J. Borkiewicz ◽  
...  
Keyword(s):  
Distribution Function ◽  
Detailed Analysis ◽  
Pair Distribution Function ◽  
Function Analysis ◽  
Electrochemical Reactions ◽  
Fluoride Ion ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pdf Analysis

Detailed analysis of electrochemical reactions occurring in rechargeable Fluoride-Ion Batteries (FIBs) is provided by means of synchrotron X-ray diffraction (XRD) and Pair Distribution Function (PDF) analysis.

Sign in / Sign up

Export Citation Format

Share Document