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This article demonstrates spatial mapping of the local and nanoscale structure of thin film objects using spatially resolved pair distribution function (PDF) analysis of synchrotron X‐ray diffraction data. This is exemplified in a lab‐on‐chip combinatorial array of sample spots containing catalytically interesting nanoparticles deposited from liquid precursors using an ink‐jet liquid‐handling system. A software implementation is presented of the whole protocol, including an approach for automated data acquisition and analysis using the atomic PDF method. The protocol software can handle semi‐automated data reduction, normalization and modeling, with user‐defined recipes generating a comprehensive collection of metadata and analysis results. By slicing the collection using included functions, it is possible to build images of different contrast features chosen by the user, giving insights into different aspects of the local structure. [ABSTRACT FROM AUTHOR]

The structure of CaO–Al2O3–B2O3–BaO glassy slags with varying mass ratio of BaO to CaO has been investigated by Raman spectroscopy, 11B and 27Al magic angle spinning nuclear magnetic resonance (MAS‐NMR) spectroscopy and atomic pair distribution function (PDF). 11B MAS‐NMR spectra reveal the dominant coordination of boron as trigonal. Both simulations on 11B MAS‐NMR spectra and Raman spectroscopy indicate the presence of orthoborate as the primary borate group with a few borate groups with one bridging oxygen and minor four‐coordinated boron sites. 27Al MAS‐NMR and PDF show the Al coordination as tetrahedral. Raman spectral study shows that the transverse vibration of AlIV–O–AlIV and AlIV–O–BIII, stretching vibration of aluminate structural units and vibration of orthoborate and pyroborate structural groups. A broader distribution of Al–O bond lengths in PDF also supports the enhanced network connectivity. Viscosity measurements show the increase in viscosity of molten slags with increasing mass ratio of BaO to CaO, which further attributes to the enhanced degree of polymerization of the aluminate network. [ABSTRACT FROM AUTHOR]

The formation of iron phosphide nanoparticles (FexP NPs) is a well‐studied process. It usually uses air‐sensitive phosphorus precursors such as n‐trioctylphosphine or white phosphorus. In this study, we report the synthesis and characterization of a remarkably stable tetrakis(acyl)cyclotetraphosphane, P4(MesCO)4. We demonstrate that this compound can be used as a stoichiometric source of P(0) species in order to synthesize FeP and Fe2P nanoparticles at only 250 °C. This tunable process provides a route to monodisperse nanoparticles with different compositions and crystallinities. We combine X‐Ray photoelectron spectroscopy (XPS) and atomic pair distribution function (PDF) in order to study the local order and bonding in the amorphous and crystalline materials. We show that crystalline FeP forms via an intermediate amorphous phase (obtained at a lower temperature) that presents local order similar to that of the crystalline sample. From the results of this work, a better understanding of the mechanism of the formation of amorphous and crystalline FexP NPs is provided which relies on the use of a stoichiometric and single P‐source. We then explore the electrocatalytic properties of FexP nanoparticles for the hydrogen evolution reaction (HER) in acidic and neutral electrolytes. In both electrolytes, amorphous FeP is a more efficient catalyst than crystalline FeP, itself more efficient than crystalline Fe2P. Our study paves the way for a more systematic investigation of amorphous metal phosphide phases in electrocatalysis. It also shows the beneficial properties of PDF on the characterization of such nanomaterials, which is highly challenging. [ABSTRACT FROM AUTHOR]

Total scattering measurements enable understanding of the structural disorder in crystalline materials by Fourier transformation of the total structure factor, S(Q), where Q is the magnitude of the scattering vector. In this work, the direct calculation of total scattering from a crystalline structural model is proposed. To calculate the total scattering intensity, a suitable Q‐broadening function for the diffraction profile is needed because the intensity and the width depend on the optical parameters of the diffraction apparatus, such as the X‐ray energy resolution and divergence, and the intrinsic parameters. X‐ray total scattering measurements for CeO2 powder were performed at beamline BL04B2 of the SPring‐8 synchrotron radiation facility in Japan for comparison with the calculated S(Q) under various optical conditions. The evaluated Q‐broadening function was comparable to the full width at half‐maximum of the Bragg peaks in the experimental total scattering pattern. The proposed calculation method correctly accounts for parameters with Q dependence such as the atomic form factor and resolution function, enables estimation of the total scattering factor, and facilitates determination of the reduced pair distribution function for both crystalline and amorphous materials. [ABSTRACT FROM AUTHOR]

This work reports the setting up of the X-ray diffraction and spectroscopy beamline at the Brazilian Synchrotron Light Laboratory for performing total scattering experiments to be analyzed by atomic pair distribution function (PDF) studies. The results of a PDF refinement for Al2O3 standard are presented and compared with data acquired at a beamline of the Advanced Photon Source, where it is common to perform this type of experiment. A preliminary characterization of the Pb1- xLa xZr0.40Ti0.60O3 ferroelectric system, with x = 0.11, 0.12 and 0.15, is also shown. [ABSTRACT FROM AUTHOR]

The crystal structures of a series of pyridine coordination polymers [ MIICl2(C5H5N) x] n ( M = Ni, Cu), prepared via thermal decomposition are reported. [NiCl2(C5H5N)4] ( 1) decomposes stepwise via [NiCl2(C5H5N)2] n ( 2), [NiCl2(C5H5N)] n ( 3), and [NiCl2(C5H5N)2/3] n ( 4), to NiCl2 with increasing temperature. The thermal decomposition of [CuCl2(C5H5N)2] n ( 5), progresses via two polymorphs of [CuCl2(C5H5N)] n ( 6a and 6b), and [CuCl2(C5H5N)2/3] n ( 7), to CuCl2. The compounds 3, 4, and 7 were prepared as pure phases. All crystal structures were determined by X-ray powder diffraction. Notably, the crystal structures of the polymorphs 6a and 6b were determined from powder diffraction data of a mixture of both phases. Crystal structures of [ MIICl2(C5H5N) x] n with the same x, but different metal atoms (Ni, Cu) are homeotypic, compounds 4 and 7 are isotypic. Compounds with x = 1 ( 3, 6a, 6b) are composed of polymeric octahedra double chains 1∞[ MCl3/3Cl2/2(C5H5N)] and in case of x = 2/3 ( 4, 7) of triple chains. The Jahn-Teller distortion in the copper compounds was observable with the pair distribution function (PDF) analysis. [ABSTRACT FROM AUTHOR]

Presents the abstract of the research paper "PDFgetX2: A GUI-driven program to Obtain the Pair Distribution Function From X-ray Powder Diffraction Data," by Xiangyun Qiu, Jeroen W. Thompson and Simon J. L. Billinge.