I11-High Resolution Powder Diffraction
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Nataliya L.
Gulay
,
Hai
Lin
,
Batoul
Almoussawi
,
Cara J.
Hawkins
,
Manel
Sonni
,
Marco
Zanella
,
Troy D.
Manning
,
Luke M.
Daniels
,
Matthew S.
Dyer
,
John B.
Claridge
,
Matthew J.
Rosseinsky
Diamond Proposal Number(s):
[36629, 37989]
Open Access
Abstract: During the exploration of the interface between the known structures of perovskite Y2NiTiO6 and hexagonal layered Y2CuTiO6, we have discovered the new phase Y10NixCu1–xTi4O24 (x = 0, 0.5, 1). The structure of Y10CuTi4O24 was solved by means of single-crystal X-ray diffraction, which revealed a layered monoclinic structure, with the space group C2/m, a = 12.2405(1), b = 5.8643(1), c = 7.1729(1) Å, β = 107.083(1)°. The structures of three Y10NixCu1–xTi4O24 (x = 0, 0.5, 1) phases were also refined based on high-resolution powder X-ray diffraction data. Substitution of Cu for Ni causes only minor changes in lattice and atomic parameters. The new phase is related to known Y5Mo2O12-type structures with an extra atomic position occupied by Ni/Cu in the structure of Y10NixCu1–xTi4O24 (x = 0, 0.5, 1). The high-resolution powder X-ray diffraction data revealed peak broadening for the reflections with l = 2n + 1 corresponding to stacking faults originating from the layered structure of Y10NixCu1–xTi4O24. Y10NixCu1–xTi4O24 (x = 0, 0.5, 1) were characterized with respect to their magnetic and optical properties.
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Jul 2026
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I11-High Resolution Powder Diffraction
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Robert D.
Smyth
,
Bradley C.
Sheath
,
Lemuel E.
Crentsil
,
Xiaoyu
Xu
,
Simon J.
Cassidy
,
Maria
Batuk
,
Pascal
Manuel
,
Emmanuelle
Suard
,
Andrew N.
Fitch
,
Joke
Hadermann
,
Simon J.
Clarke
Diamond Proposal Number(s):
[18786, 25166, 32893, 39378]
Open Access
Abstract: The contrasting crystal and magnetic structures of four related iron oxide chalcogenides are reported. Ae2FeO3CuCh (Ae = Ca, Sr; Ch = S, Se) all crystallize in the Sr2GaO3CuS structure with alkaline earth iron oxide layers containing double layers of linked FeO5 square pyramids containing Fe3+ ions separated by antifluorite-type [Cu2Ch2]2– layers. Structural distortions occur below room temperature when the small Ca2+ ions are present, and these involve cooperative tilting of the FeO5 square pyramids. Magnetic reflections present in the diffraction patterns can be indexed using either √2a × √2a × c or √2a × √2a × 2c expansions of the nuclear cell with nearest-neighbor Fe3+ moments coupling antiferromagnetically and with temperature-dependent orientations relative to the crystallographic directions. The magnetic structures of these compounds are subtly different in detail, partly on account of the low directional preference of the high-spin d5 Fe3+ moments.
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Jun 2026
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I03-Macromolecular Crystallography
I24-Microfocus Macromolecular Crystallography
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Diamond Proposal Number(s):
[31353, 38144]
Open Access
Abstract: Iron–sulfur (Fe-S) clusters are ubiquitous as redox-active protein cofactors, but it is often difficult to collect protein structures in which redox centres are in uniform and well-defined oxidation states. Using spinach ferredoxin I (Fdx) as a model redox protein, we demonstrate an integrated methodological pathway for electrochemical modulation of redox state in protein crystals coupled with in crystallo EPR and online-UV-visible spectroscopy to verify oxidation state. We show that Fdx crystals can be electrochemically reduced, reversibly, without compromising lattice integrity or X-ray diffraction quality. We show that redox levels can be precisely ascertained in crystallo via EPR and UV-visible spectroscopy, enabling a direct correlation between protein structure and electronic state of the metal cluster. In this way, we generate and compare ’oxidised’, ‘reduced’ and ‘re-oxidised’ structures of Fdx. Overall, our approach demonstrates a pipeline which will be applicable to structure-function studies of a wide range of electron-transfer proteins and redox enzymes.
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May 2026
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I15-Extreme Conditions
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Diamond Proposal Number(s):
[29285]
Open Access
Abstract: We investigate the pressure-induced structural deformations in a series of rutile-like network materials, M(dca)2 (M = Mn, Fe, Ni), using synchrotron high-pressure powder X-ray diffraction (HP-PXRD). These materials adopt an orthorhombic structure (space group Pnnm) at ambient conditions. All compounds exhibit negative linear compressibility (NLC) along the c-axis in their orthorhombic phase (M(dca)2-I), with magnitudes varying across the series: Mn(dca)2 displays the largest NLC of -10(3) TPa-1 (0.04-0.3 GPa), while Ni(dca)2 and Fe(dca)2 show -2.5(8) TPa-1 (0.07-1.06 GPa) and -2.8(4) TPa-1 (0.03-0.95 GPa), respectively. At higher pressures, these compounds undergo second-order phase transitions to a monoclinic structure (P21/c), with transition pressures dependent on the metal cation.
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Apr 2026
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[41568]
Open Access
Abstract: In this study, we explore the coordination complexes of the resorcinol bis(diphenylphosphinite) (POCOP) pincer ligand with Group 13 (aluminum, gallium and indium) metal centers. We report the synthesis of six new Group 13 POCOP complexes that have all been structurally characterized. The aluminum and indium complexes all crystallize in a five-coordinate “closed” geometry; however, for gallium, an “open” four-coordinate complex is additionally observed in the solid state, similar to an intramolecular frustrated Lewis pair.
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Apr 2026
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B24-Cryo Soft X-ray Tomography
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Edward C.
Lant
,
Archana C.
Jadhav
,
Annabel
Sumeray
,
Gustavo F.
Trindade
,
Luca
Craciunescu
,
Andrew W.
Prentice
,
Juliusz A.
Wolny
,
Jaspreet S.
Grewal
,
Robert
Dallmann
,
Guy J.
Clarkson
,
Ann M.
Dixon
,
Volker
Schünemann
,
Ian S.
Gilmore
,
Martin J.
Paterson
,
Maria
Harkiolaki
,
Peter J.
Sadler
Diamond Proposal Number(s):
[32778]
Open Access
Abstract: An integrated multimodal imaging workflow of cryogenic super-resolution fluorescence microscopy and soft X-ray tomography, Orbitrap secondary ion mass spectrometry, and inductively coupled plasma-mass spectrometry has revealed the unexpected targeting of a half-sandwich cyclopentadienyl Rh(III) phenylazopyridine anticancer complex to cellular lipid membranes and lipid droplets. The complex accumulates in plasma membranes with a surprisingly intense switch-on luminescence in living cancer cells, drives remodeling of lipid droplet architecture, and penetrates deeply into lipid-rich tissue environments. DFT modeling shows strong supramolecular interactions between the complex and glycerophosphorylcholine lipids.
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Mar 2026
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I09-Surface and Interface Structural Analysis
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Isabel
Huck
,
Niels
Kubitza
,
Tom
Keil
,
Marius
Schlapp
,
Robert
Winkler
,
Prajna
Bhatt
,
Christoph
Schlueter
,
Pardeep K.
Thakur
,
Tien-Lin
Lee
,
Paweł P.
Michałowski
,
Leopoldo
Molina-Luna
,
Anna
Regoutz
,
Christina S.
Birkel
Diamond Proposal Number(s):
[36180]
Abstract: MAX phases are an extremely versatile family of layered compounds that usually consist of an early to-mid transition metal (M-element), a main group element (mainly groups 13–15) or late transition metal (A-element) and carbon and/or nitrogen (X-element). It is therefore not too surprising that in addition to the roughly 70 compounds with 211 stoichiometry, there exist many solid solutions with mixed elements on the M- and A-site, respectively. Much less common are solid solution phases with mixed elements on both M- and A-site simultaneously (double-site solid solutions), as well as solid solutions on the X-site (carbonitride MAX phases). Challenging these restrictions in the chemical composition space, we present here for the first time (V0.2Cr0.8)2(Ga0.5Ge0.5)(C0.6N0.4) as a new carbonitride member of the MAX phase family, containing solid solutions on all three lattice sites simultaneously. This triple-site solid solution MAX phase is synthesized by high-temperature solid-state methods, and we demonstrate that it is possible to use two different nitrogen-containing precursors (VN and Cr2N), respectively. Structure, morphology and chemical composition are characterized by X-ray powder diffraction (XRD), electron microscopy (SEM/TEM), secondary ion mass spectrometry (SIMS), and X-ray photoelectron spectroscopy (HAXPES).
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Feb 2026
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B07-C-Versatile Soft X-ray beamline: Ambient Pressure XPS and NEXAFS
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John H.
Burke
,
Maren
Johnsen
,
Rachel F.
Wallick
,
Richard
Gnewkow
,
Dae Young
Bae
,
Aswin
Jyothilakshmi Ravi
,
Thomas C.
Rossi
,
Sebastian
Eckert
,
Mattis
Fondell
,
Matthijs A.
Van Spronsen
,
Richard D.
Schaller
,
Victor
Sosa Alfaro
,
Sang-Jun
Lee
,
Leland B.
Gee
,
Liviu M.
Mirica
,
Renske M.
Van Der Veen
,
Josh
Vura-Weis
Diamond Proposal Number(s):
[33855, 33267]
Abstract: Recent advancements in photocatalysis, photovoltaics, and quantum information science take advantage of electron spin, and determining how spin multiplicity affects electron transfer is key to understanding these phenomena. In this study, we examine how metal spin state affects electronic communication in an organometallic mixed-valence dimer, ferrocenyl cobaltocenium ([FeIICp2CoIIICp2]+). This complex can be photoexcited from its low-spin singlet FeII ground state to form intermediate-spin triplet FeII and high-spin quintet FeII excited states. Using femtosecond optical transient absorption (OTA) spectroscopy with visible (vis), near-infrared (NIR), and short-wave IR (SWIR) probes, supported by time-dependent density functional theory (TD-DFT) calculations, we measure FeIICoIII→FeIIICoII intervalence charge transfer (IVCT) bands in each of the FeII spin states. Mulliken–Hush analysis of the excited-state IVCT bands was used to compute the electronic coupling between the metal centers in all three spin states, which increased as quintet < triplet < singlet. Meanwhile, the peak energy of the bands, and thus the ΔG of the IVCT transition, increased as triplet < quintet < singlet. Then, to directly probe the electronic structure at each metal center, we employed picosecond soft X-ray transient absorption (XTA) spectroscopy at the Fe and Co L3 edges. Our results show that the low-spin and high-spin states of [FeIICp2CoIIICp2]+ are valence-localized, while the intermediate-spin state is partially delocalized. The differences in charge delocalization are attributed to differences in orbital occupation and geometry that affect the free energy and superexchange coupling.
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Jan 2026
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I09-Surface and Interface Structural Analysis
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Arya
Loloee
,
Manuel
Scharrer
,
Tullio S.
Geraci
,
Hui-Fei
Zhai
,
Matt S.
Flores
,
Prajna
Bhatt
,
Aysha A.
Riaz
,
Pardeep K.
Thakur
,
Tien-Lin
Lee
,
Anna
Regoutz
,
Jakoah
Brgoch
,
Jason F.
Khoury
,
Alexandra
Navrotsky
,
Christina S.
Birkel
Diamond Proposal Number(s):
[34325]
Abstract: MAX phases are a class of compounds known for having both metallic and ceramic properties, such as good electrical conductivity, oxidation resistance, and high hardness. The bulk of the research on their properties focuses on those with titanium at the M-site and metals from groups 13 to 15, e.g., aluminum, at the A-site. Here, we expand the properties repertoire with new arsenic-containing A-site solid solutions, V2(As1–xPx)C and V2(As1–xGex)C. The structure and elemental composition of the solid solutions were resolved with powder X-ray diffraction, scanning electron microscopy with energy-dispersive X-ray spectroscopy, and hard X-ray photoelectron spectroscopy. The electrical resistivity measurements show that both full series are metallic with the parent phases being the most conductive. Thermal analyses show V2GeC is the most oxidation resistant and V2AsC is the least, while substitutions decrease thermal stability, as oxidation resistance of the intermediate compositions shifts toward that of V2AsC. The V2(As1–xGex)C series shows little variation in hardness across compositions, while the incorporation of phosphorus noticeably increases hardness.
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Jan 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Caleb J.
Bennett
,
Neha
Bura
,
Frederick P.
Marlton
,
Wen Liang
Tan
,
Tobias A.
Bird
,
Pablo
Botella
,
Peijie
Zhang
,
Benedito Donizeti
Botan-Neto
,
Jose Luis
Rodrigo Ramon
,
Catalin
Popescu
,
Frederico
Alabarse
,
Daniel
Errandonea
,
Brendan J.
Kennedy
Diamond Proposal Number(s):
[36827]
Abstract: A variable temperature X-ray total-scattering study of K2IrCl6 reveals compelling evidence for local symmetry breaking in this material. While the average crystal structure remains cubic down to 11 K, consistent with earlier reports, large anisotropic chloride displacements suggest short-range distortions of the IrCl6 octahedra. Pair distribution function analysis confirms that the local structure is better described by a monoclinic P21/n model featuring a mix of in-phase and out-of-phase octahedral tilts. This behavior mirrors observations in related K2MX6 halides, where thermally driven cubic-to-monoclinic transitions occur. High-pressure synchrotron measurements further reveal two structural transitions: cubic Fm3̅m to tetragonal P4/mnc at 12.0 GPa, and tetragonal to monoclinic P21/n at 15.1 GPa. Both transitions are reversible on decompression. Lattice parameter refinements indicate anisotropic compression with the bulk modulus increasing dramatically from 23 GPa in the cubic phase to 121 GPa in the monoclinic structure. These results demonstrate that both temperature reduction and applied pressure drive K2IrCl6 toward lower-symmetry phases. Overall, this study provides the first direct local-structure evidence of symmetry breaking in K2IrCl6 and highlights the complex interplay among pressure, temperature, and local structure in vacancy-ordered double perovskites.
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Jan 2026
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