I15-1-X-ray Pair Distribution Function (XPDF)
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Céline
Crépisson
,
Mila
Fitzgerald
,
Domenic
Peake
,
Patrick G.
Heighway
,
Thomas
Stevens
,
Adrien
Descamps
,
David
Mcgonegle
,
Alexis
Amouretti
,
Karim K.
Alaa El-Din
,
Michal
Andrzejewski
,
Sam
Azadi
,
Erik
Brambrink
,
Carolina
Camarda
,
David A.
Chin
,
Samuele
Di Dio Cafiso
,
Ana
Coutinho Dutra
,
Hauke
Höppner
,
Kohdai
Yamamoto
,
Phani S.
Karamched
,
Zuzana
Konôpková
,
Motoaki
Nakatsutsumi
,
Norimasa
Ozaki
,
Danae N.
Polsin
,
Jan-Patrick
Schwinkendorf
,
Georgiy
Shoulga
,
Cornelius
Strohm
,
Minxue
Tang
,
Harry
Taylor
,
Monika
Toncian
,
Yizhen
Wang
,
Jin
Yao
,
Gianluca
Gregori
,
Justin S.
Wark
,
Karen
Appel
,
Marion
Harmand
,
Sam M.
Vinko
Diamond Proposal Number(s):
[39017]
Open Access
Abstract: Oxygen and other light elements comprise up to 5 wt% of the Earth’s outer-core, and may significantly influence its physical properties and the operation of the geodynamo. Here we report in situ X-ray diffraction measurements of Fe, Fe + 4.5 FeO (atomic proportion), and Fe2O3 melts at 177-440 GPa, achieved using laser-driven shock compression at an x-ray free-electron laser. The melts exhibit Fe-O coordination numbers between 4.0(0.4) and 4.5(0.4), indicating predominantly four-fold coordination environments. These coordination states are significantly smaller than those of Fe-bearing lower-mantle phases such as bridgmanite and ferropericlase. Shorter Fe-Fe interatomic distances in compressed iron oxide melts drive the denser packing relative to ambient melts, while the structural differences between Fe + 4.5 FeO and Fe2O3 melts under shock indicate that the oxidation state modulates oxygen solubility in liquid Fe. At 177 GPa ( ~ 380 km below the core-mantle boundary) and 3800 K, Fe2O3 melts exhibit higher Fe-O coordination, suggesting that local variations in oxygen content could contribute to the stratification in the uppermost outer-core inferred from seismological and geomagnetic observations.
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Jul 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Diamond Proposal Number(s):
[37410]
Open Access
Abstract: Chlorosulfonic acid is a superacid widely used as a sulfonating and chlorosulfonating agent. Here, we have used total neutron and X-ray scattering to understand its intra- and intermolecular structure, and interactions in the liquid phase. The behavior is dominated by very short hydrogen bonds between the hydroxyl groups and the sulfonyl oxygens (H···Ooxo 1.43 Å and 1.66 Å), comparable in length to intramolecular hydrogen bonds, with the resulting coordination number of 0.96 of sulfonyl oxygen around hydrogen below 2 Å. The hydrogen bonding leads to formation of branched head-to-tail chains and the intramolecular structure distorts to give three near-equal S–O bond lengths, consistent with the superacid’s low viscosity and high acidity.
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Jul 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Diamond Proposal Number(s):
[21714]
Open Access
Abstract: The environmental urgency to replace toxic lead-based piezoelectrics like Pb(Zr,Ti)O3 has driven the development of lead-free alternatives such as BiFeO3–BaTiO3 ceramics. While macroscopic structural optimization has yielded promising electrostrain performance, the role of the local structure remains underexplored. This study presents the first thermally induced investigation of the local structural behavior in Nd(Mg2/3Nb1/3)O3-doped BiFeO3–BaTiO3 ceramics using synchrotron x-ray pair distribution function (XPDF) analysis coupled with Raman spectroscopy. XPDF analysis reveals a dominant short-range tetragonal phase that undergoes a local phase transition near 200°C, marked by changes in lattice distortion and tetragonality. Complementary Raman spectroscopy and principal component analysis confirm spectral anomalies and phonon mode coupling in the same temperature range, indicating a potential local structural transition. These findings provide critical insights into the temperature stability and local phase dynamics of BiFeO3-based ceramics, offering a pathway to high-temperature lead-free piezoelectric applications.
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Jul 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Clara
Chinchilla-Garzó
,
Eva
Rivera-Chao
,
Miguel
Gomez-Mendoza
,
Bruno J. C.
Vieira
,
Neyvis
Almora-Barrios
,
Pol
Gimeno-Fonquernie
,
Javier
Castells-Gil
,
Rebecca
Vismara
,
Jan
Navrátil
,
Piotr
Błoński
,
Víctor A.
De La Pena O'Shea
,
João C.
Waerenborgh
,
Carlos
Marti-Gastaldo
,
Natalia
M. Padial
Diamond Proposal Number(s):
[40138]
Abstract: Photoredox catalysis has emerged as a powerful strategy for promoting redox reactions under mild conditions, but its translation from homogeneous to heterogeneous catalysts in porous solids remains limited. Metal-organic frameworks (MOFs) offer unique opportunities to bridge this gap by combining tailorable photoactive architectures with high stability, large surface areas, and modular control over reactivity via component selection. Despite recent progress, most photocatalytic MOF-based systems have focused on water splitting or CO2 reduction, whereas applications in organic synthesis remain virtually unexplored. Here, we report a titanium-iron MOF (MUV-1001) built from heterometallic TiFe2 metal-oxo clusters that operates as an intrinsically active visible-light photoredox catalyst. This platform enables single-electron transfer reactivity under irradiation, as demonstrated in a decarboxylative Giese reaction, and it represents an example of noble-metal- and additive-free C–C bond formation mediated by a pristine crystalline reticular material. Our findings highlight the potential of cluster-based design to access intrinsically photoactive systems, where subtle changes in composition dictate reactivity, even across isostructural families.
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Jun 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Laura G.
Graversen
,
Nicolas
Schlegel
,
Freja B.
Holde
,
Adrian
Sanz Arjona
,
Stefanie
Punke
,
Tobias M.
Nielsen
,
Andy S.
Anker
,
Jonas
Forner
,
Gustav K. H.
Wiberg
,
Matthias
Arenz
,
Rebecca K.
Pittkowski
,
Kirsten M. Ø.
Jensen
Diamond Proposal Number(s):
[30653]
Open Access
Abstract: Iridium oxide nanoparticles are efficient catalysts for the acidic oxygen evolution reaction (OER). We present a straightforward one-pot hydrothermal synthesis method to produce sub-1 nm Ir oxide nanoparticles in a single step, with size control achieved through post-synthesis annealing. By combining X-ray total scattering and pair distribution function (PDF) analysis with small-angle X-ray scattering (SAXS), we find that the sub-nanometer-sized oxide has an increased number of edge-sharing [IrO6]-octahedra compared to the thermodynamically favorable rutile structure. PDF modelling using various cluster motifs reveals that a sheet-like cluster, derived from rutile and comprising seven [IrO6]-octahedra with a (110)-exposed surface, can describe the increased Ir–Ir edge-sharing connectivity. We further find that cluster growth leads to a decrease in the number of edge-sharing motifs, going towards the bulk rutile structure upon annealing. Operando X-ray total scattering and PDF analysis during OER reveal high structural stability of the ultra-small (<3 nm) Ir oxides.
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Jun 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Diamond Proposal Number(s):
[35312]
Abstract: Lithium batteries with enhanced energy density and safety require solid electrolytes having stability with High voltage cathodes and Li metal. Here, halide solid electrolyte Li3YCl6 is doped with Fluorine to simultaneously increase the cathodic and anodic stability. The anodic and cathodic stability was confirmed cyclic voltammetry, impedance spectroscopy and operando pressure measurement. Further, operando X-ray photoelectron spectroscopy (XPS) during Li plating on Li3YCl5.9F0.1 was done to study effect of Fluorine on reaction kinetics driving the evolution of interphase with Li metal and its composition. Li3YCl5.9F0.1 shows stable plating striping for more than 500 h and has very high critical current density of 8 mA/cm2. Li3YCl5.9F0.1 based ASSB operating at high voltage of 4.8 V vs Li maintains a high discharge capacity of 124 mAhg-1 at C/3 rate at room temperature after 180 cycles confirming excellent electrochemical performance. Further, Li3YCl5.9F0.1 as separator enable Li metal based ASSB.
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May 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Pascal
Kolodzeiski
,
Benjamin M.
Gallant
,
Lennard
Richter
,
Mario Antonio T.
Ongkiko
,
Carlo
Franke
,
Aleksander
Kostka
,
Wen-Long
Xue
,
Chinmoy
Das
,
Jan-Benedikt
Weiss
,
Elena
Kolodzeiski
,
Thomas
Kress
,
Gregor
Kieslich
,
Tong
Li
,
Andrew J.
Morris
,
Dominik
Kubicki
,
Sebastian
Henke
Diamond Proposal Number(s):
[31642]
Open Access
Abstract: Modifying glass compositions is key to creating silicate-based glasses for technologies including optical fibres, catalytic supports, protective coatings and separation membranes. Here we extend this concept to metal–organic framework (MOF) glasses by modifying the MOF glass former ZIF-62 with Li(bim) and Na(bim) as compatible glass modifiers (benzimidazolate, bim−). Melt-quenching of physical mixtures with increasing Na(bim) content yields modified MOF glasses that exhibit a systematic decrease in the glass transition temperature (Tg), accompanied by increased liquid fragility, configurational heat capacity at Tg and density: paralleling silicate glass chemistry through partial network depolymerization. Structural and spectroscopic analysis, coupled with density-functional theory calculations, confirm that Na(bim) is incorporated homogeneously into the MOF glass framework rather than the pores and reveal the presence of undercoordinated sodium ion environments. Finally, extraction of the modifier by water treatment increases glass porosity, akin to established borosilicate glass processes. This work introduces a transferable approach for tailoring the structure and properties of MOF glasses.
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May 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Diamond Proposal Number(s):
[22843]
Open Access
Abstract: Neutron scattering with isotopic substitution and high-energy X-ray scattering have been used to evaluate the ordering of the polar solvent, dimethylformamide (DMF), around the surface of dispersed graphene oxide (GO) nanosheets. Empirical potential structural refinement (EPSR) has been used to model the interaction of this technically important material with the solvent. In reciprocal space, both neutron and X-ray scattering patterns show significant differences between the GO solution and the solvent. In real space, these differences in structure persist to at least 5 Å from the GO surface, and some changes to the solvent structure are discernible to 10 Å. EPSR modelling of the solvent interaction was undertaken using a supercell generated from the GO surface, extended in the z-direction and filled with DMF molecules. Two different GO surfaces were used: one with a random distribution of epoxide and hydroxide functional groups and one in which the arrangement was semi-ordered. There is no apparent influence of the arrangement of the functional groups on the modelled structure. The z-dependent distribution functions indicate that the oxygen atoms within the DMF molecule are closest to the nanosheet surface, implying that the solvent ordering reflects a small positive charge to the GO surface.
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Apr 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Diamond Proposal Number(s):
[37864]
Open Access
Abstract: Contamination of surface and groundwater sources by emerging persistent pollutants has presented a global environmental challenge that demands advanced remediation materials. This work exploits the large mesopores and unsaturated inorganic nodes in MIP-206-based metal–organic frameworks (MOFs) for the highly efficient adsorption of perfluorocarboxylic acids (PFCAs) from water. The materials display excellent performance for long-chain PFCAs, achieving removal efficiencies up to >99% within seconds. Detailed mechanistic studies, including synchrotron analyses, provide key insights into the development of optimized PFCA sorbents via multiple interaction types
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Apr 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Diamond Proposal Number(s):
[30870]
Open Access
Abstract: Electrochemical flash sintering (EFS) is a newly developed, solvent-free technique for ultrafast (∼2 s) densification of lithium-containing solid-state battery materials. Unlike conventional flash sintering—which relies on uncontrolled thermal runaway and requires high electronic conductivity—EFS couples electronic conduction in mixed conductors with Li+ transport across interfaces with pure ionic conductors in composite or multilayer architectures. Using spatially resolved synchrotron total scattering and pair distribution function analysis, we elucidate the mechanisms of EFS, contrasting them with conventional flash sintering of single-phase materials. Under conventional conditions, Li3V2(PO4)3 (LVP) undergoes localized decomposition and cracking at low frequencies and high currents, while Li1.3Al0.3Ti1.7(PO4)3 (LATP) requires high frequencies to overcome blocking behavior—resulting in electrode melting, infiltration, and vitreous extrusion at the pellet perimeter. In contrast, EFS enables densification of LVP–LATP composites at lower frequencies that fail for either phase alone, with reactions confined to localized hotspots. In an LVP–LATP|LATP|LVP–LATP multilayer, decomposition products are more broadly distributed, including vanadium migration into the electrolyte; nonetheless, no preferential cracking or new phases were observed at electrode–electrolyte interfaces. These findings establish EFS as a viable one-step processing strategy for integrating (electro)chemically distinct phases and lay the groundwork for its broader adoption in the dry fabrication of solid-state electrochemical energy storage systems.
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Apr 2026
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