Laue diffraction patterns with an exposure time of ca 60 ps have been acquired at the European Synchrotron Radiation Facility (ESRF) on protein crystals by using the single-bunch mode of the storage ring. A 10 ns laser pulse initiating photodissociation was synchronized with the X-ray pulse. The potential for a quantitative detection of conformational changes in proteins on the nanosecond timescale with this technique is demonstrated using the example of carbonmonoxymyoglobin, from simulations and real data. The instrumental aspects of the experiment (highly intense X-ray beam, fast shutter system, Laue camera, detector, laser apparatus and synchronization technique) are emphasized.
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http://dx.doi.org/10.1107/S090904959501661X | DOI Listing |
Materials (Basel)
January 2025
Institut Laue-Langevin (ILL), 71 Avenue des Martyrs, 38042 Grenoble Cedex 9, France.
Intense sources of very cold neutrons (VCNs) would be beneficial for various neutron scattering techniques and low-energy particle physics experiments. Binary clathrate hydrates hosting deuterated tetrahydrofuran (THF-d) and dioxygen show promise as potential moderators for such sources due to a rich spectrum of localized low-energy excitations of the encaged guest molecules. In this article, we present a reliable manufacturing technique for such hydrates.
View Article and Find Full Text PDFStruct Dyn
January 2025
Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
Sub-ångström spatial resolution of electron density coupled with sub-femtosecond to few-femtosecond temporal resolution is required to directly observe the dynamics of the electronic structure of a molecule after photoinitiation or some other ultrafast perturbation, such as by soft X-rays. Meeting this challenge, pushing the field of quantum crystallography to attosecond timescales, would bring insights into how the electronic and nuclear degrees of freedom couple, enable the study of quantum coherences involved in molecular dynamics, and ultimately enable these dynamics to be controlled. Here, we propose to reach this realm by employing convergent-beam x-ray crystallography with high-power attosecond pulses from a hard-x-ray free-electron laser.
View Article and Find Full Text PDFDiscov Nano
January 2025
Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049, Madrid, Spain.
Chemically tuned organic-inorganic hybrid halide perovskites based on bromide and chloride anions CH(NH)Pb(BrCl) (CH(NH): formamidinium ion, FA) have been crystallized and investigated by neutron powder diffraction (NPD), single crystal X-ray diffraction (SCXRD), scanning electron microscopy (SEM) and UV-vis spectroscopy. FAPbBr and FAPbCl experience successive phase transitions upon cooling, lowering the symmetry from cubic to orthorhombic phases; however, these transitions are not observed for the mixed halide phases, probably due to compositional disorder. The band-gap engineering brought about by the chemical doping of FAPb (BrCl) perovskites (x = 0.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Interfaces, Confinement, Matériaux et Nanostructures, 45071 Orléans Cedex 2, France.
Magnesium aluminates (MgO)(AlO) belong to a class of refractory materials with important applications in glass and glass-ceramic technologies. Typically, these materials are fabricated from high-temperature molten phases. However, due to the difficulties in making measurements at very high temperatures, information on liquid-state structure and properties is limited.
View Article and Find Full Text PDFInt J Comput Assist Radiol Surg
December 2024
High Energy Accelerator Research Organization, Tsukuba, Ibaraki, 305-0801, Japan.
Purpose: In this paper, we describe an algebraic reconstruction algorithm with a total variation regularization (ART + TV) based on the Superimposed Wavefront Imaging of Diffraction-enhanced X-rays (SWIDeX) method to effectively reduce the number of projections required for differential phase-contrast CT reconstruction.
Methods: SWIDeX is a technique that uses a Laue-case Si analyzer with closely spaced scintillator to generate second derivative phase-contrast images with high contrast of a subject. When the projections obtained by this technique are reconstructed, a Laplacian phase-contrast tomographic image with higher sparsity than the original physical distribution of the subject can be obtained.
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