Total scattering experiments on glass and crystalline materials at the ESRF on the ID11 Beamline

2014 ◽  
Vol 30 (S1) ◽  
pp. S2-S8 ◽  
Author(s):  
Andrea Bernasconi ◽  
Jonathan Wright ◽  
Nicholas Harker

ID11 is a multi-purpose high-energy beamline at the European Synchrotron Radiation Facility (ESRF). Owing to the high-energy X-ray source (up to 140 keV) and flexible, high-precision sample mounting which allows small sample–detector distances to be achieved, experiments such as total scattering in transmission geometry are possible. This permits the exploration of a wide Q range and so provides high real-space resolution. A range of samples (glasses and crystalline powders) have been measured at 78 keV, first putting the detector as close as possible to the sample (~10 cm), and then moving it vertically and laterally with respect to the beam in order to have circular and quarter circle sections of diffraction rings, with consequent QMAX at the edge of the detector of about 16 and 28 Å−1, respectively. Data were integrated using FIT2D, and then normalized and corrected with PDFgetX3. Results have been compared to see the effects of Q-range and counting statistics on the atomic pair distribution functions of the different samples. A Q of at least 20 Å−1 was essential to have sufficient real-space resolution for both type of samples while statistics appeared more important for glass samples rather than for crystalline samples.

2015 ◽  
Vol 30 (S1) ◽  
pp. S65-S69 ◽  
Author(s):  
Giorgia Confalonieri ◽  
Monica Dapiaggi ◽  
Marco Sommariva ◽  
Milen Gateshki ◽  
Andy N. Fitch ◽  
...  

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.


1999 ◽  
Vol 590 ◽  
Author(s):  
V. Petkov ◽  
S. J. L. Billinge ◽  
J. Heising ◽  
M. G. Kanatzidis ◽  
S. D. Shastri ◽  
...  

ABSTRACTResults of high-energy synchrotron radiation experiments are presented demonstrating the advantages of the high-resolution atomic Pair Distribution Function technique in determining the structure of materials with intrinsic disorder.


1999 ◽  
Vol 602 ◽  
Author(s):  
S. J. L. Billinge ◽  
V. Petkov ◽  
Th. Proffen ◽  
G. H. Kwei ◽  
J. L. Sarrao ◽  
...  

AbstractWe have measured atomic pair distribution functions (PDF) of La1−xCaxMnO3 using high energy x-ray diffraction. This approach yields accurate PDFs with very high real-space resolution. It also avoids potential pitfalls from the more usual neutron measurements that magnetic scattering is present in the measurement, that the neutron scattering length of manganese is negative leading to partial cancellation of PDF peaks, and that inelasticity effects might distort the resulting PDF We have used this to address the following questions which do not have a satisfactory answer: (1) What are the amplitudes and natures of the local Jahn-Teller and polaronic distortions in the CMR region. (2) Is the ground-state of the ferromagnetic metallic phase delocalized or polaronic. (3) As one moves away from the ground-state, by raising temperature or decreasing doping, towards the metal insulator transition, how does the state of the material evolve?


2015 ◽  
Vol 17 (27) ◽  
pp. 17838-17843 ◽  
Author(s):  
Kenta Fujii ◽  
Shinji Kohara ◽  
Yasuhiro Umebayashi

A new function, SQpeak(r); a connection between low-Q peak intensity with real space structure.


2003 ◽  
Vol 36 (6) ◽  
pp. 1342-1347 ◽  
Author(s):  
Peter J. Chupas ◽  
Xiangyun Qiu ◽  
Jonathan C. Hanson ◽  
Peter L. Lee ◽  
Clare P. Grey ◽  
...  

An image-plate (IP) detector coupled with high-energy synchrotron radiation was used for atomic pair distribution function (PDF) analysis, with high probed momentum transferQmax≤ 28.5 Å−1, from crystalline materials. Materials with different structural complexities were measured to test the validity of the quantitative data analysis. Experimental results are presented for crystalline Ni, crystalline α-AlF3, and the layered Aurivillius type oxides α-Bi4V2O11and γ-Bi4V1.7Ti0.3O10.85. Overall, the diffraction patterns show good counting statistics, with measuring time from one to tens of seconds. The PDFs obtained are of high quality. Structures may be refined from these PDFs, and the structural models are consistent with the published literature. Data sets from similar samples are highly reproducible.


1989 ◽  
Vol 166 ◽  
Author(s):  
T. Egami ◽  
B. H. Toby ◽  
W. Dmowski ◽  
Chr. Janot ◽  
J. D. Jorgensen

ABSTRACTThe use of high-energy neutrons from pulsed or hot sources allows the method of atomic pair distribution analysis to be applied to the structural determination of crystalline as well as amorphous solids. This method complements the standard crystallographic methods in studying non-periodic aspects of solids with or without long range order.


2011 ◽  
Vol 44 (4) ◽  
pp. 788-797 ◽  
Author(s):  
Katharine Mullen ◽  
Igor Levin

Information on the size and structure of nanoparticles can be obtainedviaanalysis of the atomic pair distribution function (PDF), which is calculated as the Fourier transform of X-ray/neutron total scattering. The structural parameters are commonly extracted by fitting a model PDF calculated from atomic coordinates to the experimental data. This paper discusses procedures for minimizing systematic errors in PDF calculations for nanoparticles and also considers the effects of noise due to counting statistics in total scattering data used to obtain the PDF. The results presented here demonstrate that smoothing of statistical noise in reciprocal-space data can improve the precision of parameter estimates obtained from PDF analysis, facilitating identification of the correct model (from multiple plausible choices) from real-space PDF fits.


2018 ◽  
Vol 33 (1) ◽  
pp. 11-20 ◽  
Author(s):  
Andrea Bernasconi ◽  
Jonathan Wright

Different experimental conditions at a versatile high-energy beamline equipped with a two-dimensional detector have been compared for powder diffraction and pair distribution function (PDF) experiments. In particular, sample size and sample to detector distances have been evaluated on a standard sample, to evaluate their effects in both Q and real space. Two illustrative cases are also discussed. The average structure and local distortions in a BaTiO3 powder with 100 nm particle size show that spurious ripples in the PDF are suppressed by increased counting statistics. Effects of small amounts of a crystalline impurity phase on a SiO2.Al2O3.Na2O.CaO glass have been quantified.


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