Errors in variable subscripts, equations and Fig. 8 in Section 3.2 of the article by Lotze et al. [(2024). J. Synchrotron Rad. 31, 42–52] are corrected.

The ability to freely control the polarization of X-rays enables measurement techniques relying on circular or linear dichroism, which have become indispensable tools for characterizing the properties of chiral molecules or magnetic structures. Therefore, the demand for polarization control in X-ray free-electron lasers is increasing to enable polarization-sensitive dynamical studies on ultrafast time scales. The soft X-ray branch Athos of SwissFEL was designed with the aim of providing freely adjustable and arbitrary polarization by building its undulator solely from modules of the novel Apple X type. In this paper, the magnetic model of the linear inclined and circular Apple X polarization schemes are studied. The polarization is characterized by measuring the angular electron emission distributions of helium for various polarizations using cold target recoil ion momentum spectroscopy. The generation of fully linear polarized light of arbitrary angle, as well as elliptical polarizations of varying degree, are demonstrated.

The Keck-PAD (pixel array detector) was developed at Cornell as a burst-rate imager capable of recording images from successive electron bunches (153 ns period) from the Advanced Photon Source (APS). Both Si and hole-collecting Schottky CdTe have been successfully bonded to this ASIC (application-specific integrated circuit) and used with this frame rate. The facility upgrades at the APS will lower the bunch period to 77 ns, which will require modifications to the Keck-PAD electronics to image properly at this reduced period. In addition, operation at high X-ray energies will require a different sensor material having a shorter charge collection time. For the target energy of 40 keV for this project, simulations have shown that electron-collecting CdTe should allow >90% charge collection within 35 ns. This collection time will be sufficient to sample the signal from one frame and prepare for the next. 750 µm-thick electron-collecting Schottky CdTe has been obtained from Acrorad and bonded to two different charge-integrating ASICs developed at Cornell, the Keck-PAD and the CU-APS-PAD. Carrier mobility has been investigated using the detector response to single X-ray bunches at the Cornell High Energy Synchrotron Source and to a pulsed optical laser. The tests indicate that the collection time will meet the requirements for 77 ns imaging.

Addressing the demand for high stability of beamline instruments at the SHINE facility, a high stability mirror regulating mechanism has been developed for mirror adjustments. Active mass damping was adopted to attenuate pitch angle vibrations of mirrors caused by structural vibrations. An internal absolute velocity feedback was used to reduce the negative impact of spillover effects and to improve performance. The experiment was conducted on a prototype structure of a mirror regulating mechanism, and results showed that the vibration RMS of the pitch angle was effectively attenuated from 47 nrad to 27 nrad above 1 Hz.

Bragg coherent X-ray diffraction imaging (BCDI) has emerged as a powerful technique for strain imaging and morphology reconstruction of nanometre-scale crystals. However, BCDI often suffers from angular distortions that appear during data acquisition, caused by radiation pressure, heating or imperfect scanning stages. This limits the applicability of BCDI, in particular for small crystals and high-flux X-ray beams. Here, we present a pre-processing algorithm that recovers the 3D datasets from the BCDI dataset measured under the impact of large angular distortions. We systematically investigate the performance of this method for different levels of distortion and find that the algorithm recovers the correct angles for distortions up to 16.4× (1640%) the angular step size dθ = 0.004°. We also show that the angles in a continuous scan can be recovered with high accuracy. As expected, the correction provides marked improvements in the subsequent phase retrieval.

The inherent ambiguity in reconstructed images from coherent diffraction imaging (CDI) poses an intrinsic challenge, as images derived from the same dataset under varying initial conditions often display inconsistencies. This study introduces a method that employs the Noise2Noise approach combined with neural networks to effectively mitigate these ambiguities. We applied this methodology to hundreds of ambiguous reconstructed images retrieved from a single diffraction pattern using a conventional retrieval algorithm. Our results demonstrate that ambiguous features in these reconstructions are effectively treated as inter-reconstruction noise and are significantly reduced. The post-Noise2Noise treated images closely approximate the average and singular value decomposition analysis of various reconstructions, providing consistent and reliable reconstructions.

Full-field transmission X-ray microscopy has been recently implemented at the hard X-ray ROCK–SOLEIL quick-EXAFS beamline, adding micrometre spatial resolution to the second time resolution characterizing the beamline. Benefiting from a beam size versatility due to the beamline focusing optics, full-field hyperspectral XANES imaging has been successfully used at the Fe K-edge for monitoring the pressure-induced spin transition of a 150 µm × 150 µm Fe(o-phen)2(NCS)2 single crystal and the charge of millimetre-sized LiFePO4 battery electrodes. Hyperspectral imaging over 2000 eV has been reported for the simultaneous monitoring of Fe and Cu speciation changes during activation of a FeCu bimetallic catalyst along a millimetre-sized catalyst bed. Strategies of data acquisition and post-data analysis using Jupyter notebooks and multivariate data analysis are presented, and the gain obtained using full-field hyperspectral quick-EXAFS imaging for studies of functional materials under process conditions in comparison with macroscopic information obtained by non-spatially resolved quick-EXAFS techniques is discussed.

One of the most challenging aspects of X-ray research is the delivery of liquid sample flows into the soft X-ray beam. Currently, cylindrical microjets are the most commonly used sample injection systems for soft X-ray liquid spectroscopy. However, they suffer from several drawbacks, such as complicated geometry due to their curved surface. In this study, we propose a novel 3D-printed nozzle design by introducing microscopic flat sheet jets that provide micrometre-thick liquid sheets with high stability, intending to make this technology more widely available to users. Our research is a collaboration between the EuXFEL and MAX IV research facilities. This collaboration aims to develop and refine a 3D-printed flat sheet nozzle design and a versatile jetting platform that is compatible with multiple endstations and measurement techniques. Our flat sheet jet platform improves the stability of the jet and increases its surface area, enabling more precise scanning and differential measurements in X-ray absorption, scattering, and imaging applications. Here, we demonstrate the performance of this new arrangement for a flat sheet jet setup with X-ray photoelectron spectroscopy, photoelectron angular distribution, and soft X-ray absorption spectroscopy experiments performed at the photoemission end­station of the FlexPES beamline at MAX IV Laboratory in Lund, Sweden.

Small-angle-scattering tensor tomography is a technique for studying anisotropic nanostructures of millimetre-sized samples in a volume-resolved manner. It requires the acquisition of data through repeated tomographic rotations about an axis which is subjected to a series of tilts. The tilt that can be achieved with a typical setup is geometrically constrained, which leads to limits in the set of directions from which the different parts of the reciprocal space map can be probed. Here, we characterize the impact of this limitation on reconstructions in terms of the missing wedge problem of tomography, by treating the problem of tensor tomography as the reconstruction of a three-dimensional field of functions on the unit sphere, represented by a grid of Gaussian radial basis functions. We then devise an acquisition scheme to obtain complete data by remounting the sample, which we apply to a sample of human trabecular bone. Performing tensor tomographic reconstructions of limited data sets as well as the complete data set, we further investigate and validate the missing wedge problem by investigating reconstruction errors due to data incompleteness across both real and reciprocal space. Finally, we carry out an analysis of orientations and derived scalar quantities, to quantify the impact of this missing wedge problem on a typical tensor tomographic analysis. We conclude that the effects of data incompleteness are consistent with the predicted impact of the missing wedge problem, and that the impact on tensor tomographic analysis is appreciable but limited, especially if precautions are taken. In particular, there is only limited impact on the means and relative anisotropies of the reconstructed reciprocal space maps.

Beamline BL08U1A is a soft X-ray spectromicroscopy beamline at Shanghai Synchrotron Radiation Facility (SSRF) that exhibits the capabilities of high spatial resolution (30 nm) and high energy resolving power (over 104). As a first-generation beamline of SSRF, owing to its continuous operation over the last ten years, an urgent upgrade of the equipment including the monochromator was deemed necessary. The upgrade work included the overall construction of the monochromator and replacement of the mirrors upstream and downstream of the monochromator. Based on its original skeleton, two elliptically cylinder mirrors were designed to focus the beam horizontally, which can increase the flux density by about three times on the exit slits. Meanwhile, the application of variable-line-space gratings in the monochromator demonstrates the dual functions of dispersing and focusing on the exit slits which can decrease abberations dramatically. After the upgrade of the main components of the beamline, the energy range is 180–2000 eV, the energy resolving power reaches 16333 @ 244 eV and 12730 @ 401 eV, and the photon flux measured in the experimental station is over 2.45 × 109 photons s−1 (E/ΔE = 6440 @ 244 eV).

A state-of-the-art multilayer deposition system with a 4200 mm-long linear substrate translator housed within an ultra-high vacuum chamber has been developed. This instrument is engineered to produce single and multilayer coatings, accommodating mirrors up to 2000 mm in length through the utilization of eight rectangular cathodes. To ensure the quality and reliability of the coatings, the system incorporates various diagnostic tools for in situ thickness uniformity and stress measurement. Furthermore, the system features an annealing process capable of heating up to 700°C within the load-lock chamber. The entire operation, including pump down, deposition and venting processes, is automated through user-friendly software. In addition, all essential log data, power of sputtering source, working pressure and motion positions are automatically stored for comprehensive data analysis. Preliminary commissioning results demonstrate excellent lateral film thickness uniformity, achieving 0.26% along the translation direction over 1500 mm in dynamic mode. The multilayer deposition system is poised for use in fabricating periodic, lateral-graded and depth-graded multilayers, specifically catering to the beamlines for diverse scientific applications at Diamond Light Source.

The Circular Electron–Positron Collider (CEPC) in China can also work as an excellent powerful synchrotron light source, which can generate high-quality synchrotron radiation. This synchrotron radiation has potential advantages in the medical field as it has a broad spectrum, with energies ranging from visible light to X-rays used in conventional radiotherapy, up to several megaelectronvolts. FLASH radiotherapy is one of the most advanced radiotherapy modalities. It is a radiotherapy method that uses ultra-high dose rate irradiation to achieve the treatment dose in an instant; the ultra-high dose rate used is generally greater than 40 Gy s−1, and this type of radiotherapy can protect normal tissues well. In this paper, the treatment effect of CEPC synchrotron radiation for FLASH radiotherapy was evaluated by simulation. First, a Geant4 simulation was used to build a synchrotron radiation radiotherapy beamline station, and then the dose rate that the CEPC can produce was calculated. A physicochemical model of radiotherapy response kinetics was then established, and a large number of radiotherapy experimental data were comprehensively used to fit and determine the functional relationship between the treatment effect, dose rate and dose. Finally, the macroscopic treatment effect of FLASH radiotherapy was predicted using CEPC synchrotron radiation through the dose rate and the above-mentioned functional relationship. The results show that the synchrotron radiation beam from the CEPC is one of the best beams for FLASH radiotherapy.

The development of hard X-ray nanoprobe techniques has given rise to a number of experimental methods, like nano-XAS, nano-XRD, nano-XRF, ptychography and tomography. Each method has its own unique data processing algorithms. With the increase in data acquisition rate, the large amount of generated data is now a big challenge to these algorithms. In this work, an intuitive, user-friendly software system is introduced to integrate and manage these algorithms; by taking advantage of the loosely coupled, component-based design approach of the system, the data processing speed of the imaging algorithm is enhanced through optimization of the parallelism efficiency. This study provides meaningful solutions to tackle complexity challenges faced in synchrotron data processing.

Developing new materials for Li-ion and Na-ion batteries is a high priority in materials science. Such development always includes performance tests and scientific research. Synchrotron radiation techniques provide unique abilities to study batteries. Electrochemical cell design should be optimized for synchrotron studies without losing electrochemical performance. Such design should also be compatible with operando measurement, which is the most appropriate approach to study batteries and provides the most reliable results. The more experimental setups a cell can be adjusted for, the easier and faster the experiments are to carry out and the more reliable the results will be. This requires optimization of window materials and sizes, cell topology, pressure distribution on electrodes etc. to reach a higher efficiency of measurement without losing stability and reproducibility in electrochemical cycling. Here, we present a cell design optimized for nuclear resonance techniques, tested using nuclear forward scattering, synchrotron Mössbauer source and nuclear inelastic scattering.

To date, computed tomography experiments, carried-out at synchrotron radiation facilities worldwide, pose a tremendous challenge in terms of the breadth and complexity of the experimental datasets produced. Furthermore, near real-time three-dimensional reconstruction capabilities are becoming a crucial requirement in order to perform high-quality and result-informed synchrotron imaging experiments, where a large amount of data is collected and processed within a short time window. To address these challenges, we have developed and deployed a synchrotron computed tomography framework designed to automatically process online the experimental data from the synchrotron imaging beamlines, while leveraging the high-performance computing cluster capabilities to accelerate the real-time feedback to the users on their experimental results. We have, further, integrated it within a modern unified national authentication and data management framework, which we have developed and deployed, spanning the entire data lifecycle of a large-scale scientific facility. In this study, the overall architecture, functional modules and workflow design of our synchrotron computed tomography framework are presented in detail. Moreover, the successful integration of the imaging beamlines at the Shanghai Synchrotron Radiation Facility into our scientific computing framework is also detailed, which, ultimately, resulted in accelerating and fully automating their entire data processing pipelines. In fact, when compared with the original three-dimensional tomography reconstruction approaches, the implementation of our synchrotron computed tomography framework led to an acceleration in the experimental data processing capabilities, while maintaining a high level of integration with all the beamline processing software and systems.

Xray free-electron lasers (XFELs) enable experiments that would have been impractical or impossible at conventional X-ray laser facilities. Indeed, more XFEL facilities are being built and planned, with their aim to deliver larger pulse energies and higher peak brilliance. While seeking to increase the pulse power, it is quintessential to consider the maximum pulse fluence that a grazing-incidence FEL mirror can withstand. To address this issue, several studies were conducted on grazing-incidence damage by soft X-ray FEL pulses at the European XFEL facility. Boron carbide (B4C) coatings on polished silicon substrate were investigated using 1 keV photon energy, similar to the X-ray mirrors currently installed at the soft X-ray beamlines (SASE3). The purpose of this study is to compare the damage threshold of B4C and Si to determine the advantages, tolerance and limits of using B4C coatings.

Ultra-high-speed synchrotron-based hard X-ray (i.e. above 10 keV) imaging is gaining a growing interest in a number of scientific domains for tracking non-repeatable dynamic phenomena at spatio-temporal microscales. This work describes an optimized indirect X-ray imaging microscope designed to achieve high performance at micrometre pixel size and megahertz acquisition speed. The entire detector optical arrangement has an improved sensitivity within the near-ultraviolet (NUV) part of the emitted spectrum (i.e. 310–430 nm wavelength). When combined with a single-crystal fast-decay scintillator, such as LYSO:Ce (Lu2−xYxSiO5:Ce), it exploits the potential of the NUV light-emitting scintillators. The indirect arrangement of the detector makes it suitable for high-dose applications that require high-energy illumination. This allows for synchrotron single-bunch hard X-ray imaging to be performed with improved true spatial resolution, as herein exemplified through pulsed wire explosion and superheated near-nozzle gasoline injection experiments at a pixel size of 3.2 µm, acquisition rates up to 1.4 MHz and effective exposure time down to 60 ps.

An innovative dual-thickness semi-transparent beamstop designed to enhance the performance of small-angle X-ray scattering (SAXS) experiments is introduced. This design integrates two absorbers of differing thicknesses side by side into a single attenuator, known as a beamstop. Instead of completely stopping the direct beam, it attenuates it, allowing the SAXS detector to measure the transmitted beam through the sample. This approach achieves true synchronization in measuring both scattered and transmitted signals and effectively eliminates higher-order harmonic contributions when determining the transmission light intensity through the sample. This facilitates and optimizes signal detection and background subtraction. This contribution details the theoretical basis and practical implementation of this solution at the SAXS station on the 1W2A beamline at the Beijing Synchrotron Radiation Facility. It also anticipates its application at other SAXS stations, including that at the forthcoming High Energy Photon Source, providing an effective solution for high-precision SAXS experiments.

The title compound, [RuCl2(C25H22P2)2] or [RuCl2(dppm)2] (dppm = bis­(di­phenyl­phosphan­yl)methane, C25H22P2) crystallizes as two half-mol­ecules (completed by inversion symmetry) in space group Poverline{1} (Z = 2), with the RuII atoms occupying inversion centers at 0,0,0 and 1/2, 1/2, 1/2, respectively. The bidentate phosphane ligands occupy equatorial positions while the chlorido ligands complete the distorted octa­hedral coordination spheres at axial positions. The bite angles of the phosphane chelates are similar for the two mol­ecules [(P—Ru—P)avg. = 71.1°], while there are significant differences in the twisting of the methyl­ene backbone, with a distance of the methyl­ene C atom from the RuP4 plane of 0.659 (2) and 0.299 (3) Å, respectively, and also for the phenyl substituents for both mol­ecules due to variations in weak C—H⋯Cl inter­actions.

The title compound, C16H13FN2O2, was synthesized by nucleophilic substitution of the indazole N—H hydrogen atom of methyl 1H-indazole-3-carboxyl­ate with 1-(bromo­meth­yl)-4-fluoro­benzene. In the crystal, some hydrogen-bond-like inter­actions are observed.

A second crystalline modification of the title compound, C12H19N3S [common name: cis-jasmone thio­semicarbazone] was crystallized from tetra­hydro­furane at room temperature. There is one crystallographic independent mol­ecule in the asymmetric unit, showing disorder in the cis-jasmone chain [site-occupancy ratio = 0.590 (14):0.410 (14)]. The thio­semicarbazone entity is approximately planar, with the maximum deviation from the mean plane through the N/N/C/S/N atoms being 0.0463 (14) Å [r.m.s.d. = 0.0324 Å], while for the five-membered ring of the jasmone fragment, the maximum deviation from the mean plane through the carbon atoms amounts to 0.0465 (15) Å [r.m.s.d. = 0.0338 Å]. The mol­ecule is not planar due to the dihedral angle between these two fragments, which is 8.93 (1)°, and due to the sp3-hybridized carbon atoms in the jasmone fragment chain. In the crystal, the mol­ecules are connected by N—H⋯S and C—H⋯S inter­actions, with graph-set motifs R22(8) and R21(7), building mono-periodic hydrogen-bonded ribbons along [010]. A Hirshfeld surface analysis indicates that the major contributions for the crystal cohesion are H⋯H (67.8%), H⋯S/S⋯H (15.0%), H⋯C/C⋯H (8.5%) and H⋯N/N⋯H (5.6%) [only non-disordered atoms and those with the highest s.o.f. were considered]. This work reports the second crystalline modification of the cis-jasmone thio­semicarbazone structure, the first one being published recently [Orsoni et al. (2020). Int. J. Mol. Sci. 21, 8681–8697] with the crystals obtained in ethanol at 273 K.

The reaction between a racemic mixture of (R,S)-fixolide and 4-methyl­thio­semicarbazide in ethanol with a 1:1 stoichiometric ratio and catalysed with HCl, yielded the title compound, C20H31N3S [common name: (R,S)-fixolide 4-methyl­thio­semicarbazone]. There is one crystallographically independent mol­ecule in the asymmetric unit, which is disordered over the aliphatic ring [site-occupancy ratio = 0.667 (13):0.333 (13)]. The disorder includes the chiral C atom, the neighbouring methyl­ene group and the methyl H atoms of the methyl group bonded to the chiral C atom. The maximum deviations from the mean plane through the disordered aliphatic ring amount to 0.328 (6) and −0.334 (6) Å [r.m.s.d. = 0.2061 Å], and −0.3677 (12) and 0.3380 (12) Å [r.m.s.d. = 0.2198 Å] for the two different sites. Both fragments show a half-chair conformation. Additionally, the N—N—C(=S)—N entity is approximately planar, with the maximum deviation from the mean plane through the selected atoms being 0.0135 (18) Å [r.m.s.d. = 0.0100 Å]. The mol­ecule is not planar due to the dihedral angle between the thio­semicarbazone entity and the aromatic ring, which amounts to 51.8 (1)°, and due to the sp3-hybridized carbon atoms of the fixolide fragment. In the crystal, the mol­ecules are connected by H⋯S inter­actions with graph-set motif C(4), forming a mono-periodic hydrogen-bonded ribbon along [100]. The Hirshfeld surface analysis suggests that the major contributions for the crystal cohesion are [(R,S)-isomers considered separately] H⋯H (75.7%), H⋯S/S⋯H (11.6%), H⋯C/C⋯H (8.3% and H⋯N/N⋯H (4.4% for both of them).

The reaction of ethane-1,2-di­amine (en, C2H8N2), the sodium salt of naphthalene-1,5-di­sulfonic acid (H2NDS, C10H8O6S2), and nickel sulfate in an aqueous solution resulted in the formation of the title salt, [Ni(C2H8N2)(H2O)4](C10H6O6S2)·2H2O or [Ni(en)(H2O)4](NDS)·2H2O. In the asymmetric unit, one half of an [Ni(en)(H2O)4]2+ cation and one half of an NDS2− anion, and one water mol­ecule of crystallization are present. The Ni2+ cation in the complex is positioned on a twofold rotation axis and exhibits a slight tetra­gonal distortion of the cis-NiO4N2 octa­hedron, with an Ni—N bond length of 2.0782 (16) Å, and Ni—O bond lengths of 2.1170 (13) Å and 2.0648 (14) Å. The anion is completed by inversion symmetry. In the extended structure, the cations, anions, and non-coordinating water mol­ecules are connected by inter­molecular N—H⋯O and O—H⋯O hydrogen bonding, as well as C—H⋯π inter­actions, forming a three-dimensional network.

The structure of the title compound, C9H10OTe, at 100 K has ortho­rhom­bic (P21212) symmetry with two independent mol­ecules in the asymmetric unit (Z' = 2). The mol­ecules are folded along their Te⋯O axes, with their Te–C–O planes angled at an average of 25.1° with respect to the remaining non-H atoms, which are almost coplanar (average deviation from planarity = 0.04 Å). A Hirshfeld plot shows weak inter­molecular inter­actions between the two Te atoms located in each asymmetric mol­ecule, with a Te⋯Te distance of 3.7191 (4) Å. The structure is strongly pseudosymmetric to the space group Pccn with Z' = 1. The crystal chosen for data collection was found to be was an inversion twin.

The mol­ecular structure of the solvated title salt, (C21H25N2)2[Fe2(C14H10S2)4]·2C3H7NO reveals that the anion is situated on a crystallographic inversion center in the triclinic space group Poverline{1}. The title compound crystallizes utilizing a network of weak π-stacking inter­actions of phenyl rings pertaining to the di­thiol­ene unit. Moreover, the acidic imidazolium H atoms [N—C(H)—N] display non-classical hydrogen-bonding inter­actions of the C—H⋯O type to the oxygen atoms of the N,N-dimethyl formamide solvent, and hydrogen atoms on the backbone of imidazolium rings display weak C—H⋯S inter­actions with the di­thiol­ene sulfur atoms.

The structure of the title solvated porphyrin, C56H38N8O2·C6H14, is reported. Two porphyrin mol­ecules, one ordered and one disordered n-hexane solvate mol­ecules are present in its asymmetric unit. The porphyrin macrocycle shows a characteristic saddle-shaped distortion, and the maximum deviation from the mean plane for non-hydrogen atoms is 0.48 Å. N—H⋯N, N—H⋯O, and C—H⋯O hydrogen bonds, as well as π–π inter­actions, are observed in the crystal structure.

In the paper by Oliveira et al. [IUCrData (2023), 8, x230971], there was an error in the name of the first author.

The equimolar and hydro­chloric acid-catalysed reaction between cis-jasmone and 4-methyl­thio­semicarbazide in ethano­lic solution yields the title compound, C13H21N3S (common name: cis-jasmone 4-methyl­thio­semicarbazone). Two mol­ecules with all atoms in general positions are present in the asymmetric unit. In one of them, the carbon chain is disordered [site occupancy ratio = 0.821 (3):0.179 (3)]. The thio­semicarbazone entities [N—N—C(=S)—N] are approximately planar, with the maximum deviation from the mean plane through the selected atoms being −0.0115 (16) Å (r.m.s.d. = 0.0078 Å) for the non-disordered mol­ecule and 0.0052 (14) Å (r.m.s.d. = 0.0031 Å) for the disordered one. The mol­ecules are not planar, since the jasmone groups have a chain with sp3-hybridized carbon atoms and, in addition, the thio­semicarbazone fragments are attached to the respective carbon five-membered rings and the dihedral angles between them for each mol­ecule amount to 8.9 (1) and 6.3 (1)°. In the crystal, the mol­ecules are connected through pairs of N—H⋯S and C—H⋯S inter­actions into crystallographically independent centrosymmetric dimers, in which rings of graph-set motifs R22(8) and R21(7) are observed. A Hirshfeld surface analysis indicates that the major contributions for the crystal cohesion are from H⋯H (70.6%), H⋯S/S⋯H (16.7%), H⋯C/C⋯H (7.5%) and H⋯N/N⋯H (4.9%) inter­actions [considering the two crystallographically independent mol­ecules and only the disordered atoms with the highest s.o.f. for the evaluation].

The title complex, [PdCl2(C9H13N)2], comprises a single mol­ecule in the asymmetric unit. The PdII atom is tetra­coordinated by two N atoms from two trans-aligned organic ligands and two Cl ligands, forming a square-planar metal coordination environment. The distances from the ortho-H atoms on the phenyl ring to the central PdII atom fall within the range 4.70–5.30 Å, precluding any significant intra­molecular Pd⋯H inter­actions.

In the title complex, [ZnCl2(C14H12N2O2)], the ZnII atom is located on a twofold rotation axis and is fourfold coordinated by two chlorido ligands and a bidentate 4,7-meth­oxy-1,10-phenanthroline ligand in a distorted tetra­hedral environment. Weak π–π stacking inter­actions between adjacent 4,7-dimeth­oxy-1,10-phenanthroline rings [centroid-to-centroid distances = 3.5969 (11) and 3.7738 (11) Å] contribute to the alignment of the complexes in layers parallel to (overline{2}01).

In the title compound, 2C7H7N2O+·C2O42−, proton transfer from oxalic acid to the N atom of the heterocycle has occurred to form a 2:1 molecular salt. In the extended structure, N—H⋯O hydrogen bonds link the components into [100] chains, which feature R22(8) and R44(14) loops.

The manganese title complex, [Mn(C7H5N2O4)2(C7H6N2O4)2(H2O)2]·2H2O, is one of the first 4-amino 3-nitro­benzoic acid (4 A3NBA) monoligand metal complexes to be synthesized. It crystallizes in the centrosymmetric monoclinic space group P21/n with the complex mol­ecules located on inversion centers. Four 4 A3NBA ligand mol­ecules are monodentately coordinated by the Mn2+ ion through the carb­oxy­lic oxygen atoms while the other two positions of the inner coordination sphere are occupied by water mol­ecules, giving rise to a distorted octa­hedron, and two water mol­ecules are in the outer coordination sphere. There are two intra­molecular hydrogen bonds in the complex mol­ecule. The first is of the common N—H⋯O=N type, while the second is a rarely occurring very strong hydrogen bond in which a common proton is shared by two uncoordinated oxygen atoms of neighboring carboxyl­ate groups. In the crystal, an intricate system of inter­molecular hydrogen bonds links the complex mol­ecules into a three-dimensional-network.

A new square-planar palladium complex salt hydrate, (C9H12NO)2[PdCl4]·0.5H2O, has been characterized. The asymmetric unit of the complex salt comprises two [PdCl4]2− dianions, four 2-hy­droxy-2,3-di­hydro-1H-inden-1-aminium cations, each derived from (1R,2S)-(+)-1-amino­indan-2-ol, and one water mol­ecule of crystallization. In the crystal, a two-dimensional layer parallel to (001) features a number of O—H⋯O, N—H⋯O, O—H⋯Cl and N—H⋯Cl hydrogen bonds.

In the title triazole-based N-heterocyclic carbene rhodium(I) cationic complex with a tetra­fluorido­borate counter-anion, [Rh(C8H12)(C8H15N3)(C18H15P)]BF4, which crystallizes with two cations and two anions in the asymmetric unit, the Rh center has a distorted square-planar coordination geometry with expected bond distances. Several nonclassical C—H⋯F hydrogen-bonding inter­actions help to consolidate the packing. Two of the F atoms of one of the anions are disordered over adjacent sites in a 0.814 (4):0.186 (4) ratio.

In the title complex, [Ni(C19H13N5)2](CF3SO3)2·(CH3CH2)2O, the central NiII atom is sixfold coordinated by three nitro­gen atoms of each 2,6-bis­(2-benzimidazol­yl)pyridine ligand in a distorted octa­hedral geometry with two tri­fluoro­methane­sulfonate ions and a mol­ecule of diethyl ether completing the outer coordination sphere of the complex. Hydrogen bonding contributes to the organization of the asymmetric units in columns along the a axis generating a porous supra­molecular structure. The structure was refined as a two-component twin with a refined BASF value of 0.4104 (13).

In the title complex salt, [Pd(C10H8N2)(C12H12N2O2)](CF3SO3)2, the palladium(II) atom is fourfold coordinated by two chelating ligands, 2,2'-bi­pyridine and 4,4'-dimeth­oxy-2,2'-bi­pyridine, in a distorted square-planar environment. In the crystal, weak π–π stacking inter­actions between the 2,2'-bi­pyridine rings [centroid-to-centroid distances = 3.8984 (19) Å] and between the 4,4'-dimeth­oxy-2,2'-bi­pyridine rings [centroid-to-centroid distances = 3.747 (18) Å] contribute to the alignment of the complex cations in columns parallel to the b-axis direction.

In the title complex, [Ru(C10H8N2)2(C6H6N2O)(H2O)](CF3SO3)2, the central RuII atom is sixfold coordinated by two bidentate 2,2'-bi­pyridine, an isonic­otinamide ligand, and a water mol­ecule in a distorted octa­hedral environment with tri­fluoro­methane­sulfonate ions completing the outer coordination sphere of the complex. Hydrogen bonding involving the water mol­ecule and weak π–π stacking inter­actions between the pyridyl rings in adjacent mol­ecules contribute to the alignment of the complexes in columns parallel to the c axis.

The structure of the title complex, [Zn2(C2H3O2)4(C11H9N3O)2], is triclinic containing half of the mol­ecule in the asymmetric unit. Each zinc atom is coordinated to a pyridyl and oxime nitro­gen from one di-2-pyridyl ketone oxime (dpko) ligand and a third nitro­gen from the other dpko pyridyl ring. Additionally, each zinc is coordinated to two acetato anions, one of which is bidentate and the other monodentate. The uncoordinated oxygen of the monodentate acetato group is involved in a hydrogen bond with the oxime hydrogen. The packing in the crystal is assisted by weak C—H⋯O inter­actions between acetato groups and neighboring pyridyl rings.

The title pyrene-fused spiro­pyran derivative, C30H25NO, crystallizes with two mol­ecules in the asymmetric unit with dihedral angles between their fused-ring sub units of 76.20 (8) and 89.38 (9)°. In the crystal, weak C—H⋯π inter­actions link the mol­ecules into a three-dimensional network.

The title compound, C14H12O4, comprises of two crystallographically independent mol­ecules in the asymmetric unit, linked via C—H⋯O inter­actions to form dimeric entities. The allylic groups are twisted out of the phenyl planes with dihedral angles varying between 7.92 (13) and 25.42 (8)°. In the crystal, the packing follows a zigzag pattern along the c-axis direction. The absolute configuration of the sample could not be determined reliably.

The title compound, C16H17BrO2S, crystallizes as the erythro (RR/SS) isomer of a pair of sulfones that were diastereomeric due to chirality of the α-carbon atoms on the sulfone sulfur atom. The structural analysis was pivotal in showing that the 1,3 elimination reactions of these compounds, which lead to substituted stilbenes, occur with inversion at each asymmetric carbon atom. In the crystal, C—H⋯Br and C—H⋯O hydrogen bonds link the mol­ecules into a tri-periodic inter­molecular network.

The central NiII atom in the title complex, [Ni(C13H25N2S2)2], is located on an inversion center and adopts a roughly square-planar coordination environment defined by two chelating N,S donor sets of two symmetry-related ligands in a trans configuration. The Ni—N and Ni—S bond lenghts are 1.9193 (14) and 2.1788 (5) Å, respectively, with a chelating N—Ni—S bond angle of 86.05 (4)°. These data are compared with those measured for similar di­thio­carbazato ligands that bear n-octyl or n-hexyl alkyl chains. Slight differences are observed with respect to the phenyl­ethyl­idene derivative where the ligands are bound cis relative to one another.

The structure of the title compound, [RuCl2(C7H10N2)2(C2H6OS)2], has monoclinic (P21/n) symmetry. The Ru—N distances of the coordination compound are influenced by the trans chloride or di­methyl­sulfoxide-κS ligands. The mol­ecular structure exhibits disorder for two of the terminal methyl groups of a dimethyl sulfoxide ligand.

The title compound, C13H10FNO2, was obtained by the reaction of 2-bromo-4-fluoro­benzoic acid with aniline. There are two independent mol­ecules, A and B, in the asymmetric unit, with slight conformational differences: the dihedral angles between the aromatic rings are 55.63 (5) and 52.65 (5)°. Both mol­ecules feature an intra­molecular N—H⋯O hydrogen bond. In the crystal, the mol­ecules are linked by pairwise O—H⋯O hydrogen bonds to form A–B acid–acid dimers and weak C—H⋯F inter­actions further connect the dimers.

The title compound, C13H10BrNO2, was obtained by the reaction of 2,5-di­bromo­benzoic acid and aniline. The mol­ecule is twisted with a dihedral angle between the aromatic rings of 45.74 (11)° and an intr­amolecular N—H⋯O hydrogen bond is seen. In the crystal, pairwise O—H⋯O hydrogen bonds generate carb­oxy­lic acid inversion dimers.

In the title compound, C26H18BrN, the dihedral angles between the anthracene ring system and the phenyl rings are 89.51 (14) and 74.03 (15)°. In the extended structure, a weak C—H⋯Br inter­action occurs, which generates [100] chains, but no significant π–π or C—H⋯π inter­actions are observed.

The title mol­ecule, C12H15NO5, is a methyl carbamate derivative obtained by reacting (R)-2-phenyl­glycinol and methyl chloro­formate, with calcium hydroxide as heterogeneous catalyst. Supra­molecular chains are formed in the [100] direction, based on N—H⋯O hydrogen bonds between the amide and carboxyl­ate groups. These chains weakly inter­act in the crystal, and the phenyl rings do not display significant π–π inter­actions.

The mol­ecular structure of 2-ferrocenyl-2-[(2-ferrocenylethen­yl)(morpholin-4-yl)meth­yl]-1,3-di­thiol­ane, [Fe2(C5H5)2(C19H21NOS2)] or C29H31Fe2NOS2, has the ferrocenyl fragments in a trans disposition with respect to the vinyl group. One of the methyl­ene groups is disordered over two sites with occupancies of 0.782 (13):0.218 (13). In the crystal, cyclo­penta­dienyl-C—H⋯O(morpholin­yl) inter­actions feature within helical chains parallel to the c-axis direction. The chains are connected by methyl­ene- and cyclo­penta­dienyl-C—H⋯O(cyclo­penta­dien­yl) inter­actions.

The title compound, trans-di­bromido­tetra­kis­(5-methyl-1H-pyrazole-κN2)manganese(II), [MnBr2(C4H6N2)4] or [Mn(3-MePzH)4Br2] (1) crystallizes in the triclinic Poverline{1} space group with the cell parameters a = 7.6288 (3), b = 8.7530 (4), c = 9.3794 (4) Å and α = 90.707 (4), β = 106.138 (4), γ = 114.285 (5)°, V = 542.62 (5) Å3, T = 120 K. The asymmetric unit contains only half the mol­ecule with the manganese atom is situated on a crystallographic inversion center. The 3-MePzH ligands are present in an AABB type manner with two methyl groups pointing up and the other two down. The supra­molecular architecture is characterized by several inter­molecular C—H⋯N, N—H⋯Br, and C—H⋯π inter­actions. Earlier, a polymorphic structure of [Mn(3-MePzH)4Br2] (2) with a similar geometry and also an AABB arrangement for the pyrazole ligands was described [Reedijk et al. (1971). Inorg. Chem. 10, 2594–2599; a = 8.802 (6), b = 9.695 (5), c = 7.613 (8) Å and α = 105.12 (4), β = 114.98 (4), γ = 92.90 (3)°, V = 558.826 (5) Å3, T = 295 K]. A varying supra­molecular pattern was reported, with the structure of 1 featuring a herringbone type pattern while that of structure 2 shows a pillared network type of arrangement along the a axis. A nickel complex [Ni(3-MePzH)4Br2] isomorphic to 1 and the analogous chloro derivatives of FeII, CoII and CuII are also known.

The structure of the title compound, [C14H18N2)2Ag2](NO3)2, contains subtle differences in ligand, metal, and counter-anion coordination. One quinoxaline ligand uses one of its quinoxaline N atoms to bond to one silver cation. That silver cation is bound to a second quinoxaline which, in turn, is bound to a second silver atom; thereby using both of its quinoxaline N atoms. A nitrate group bonds with one of its O atoms to the first silver and uses the same oxygen to bond to a silver atom (related by symmetry to the second), thereby forming an extended network. The second nitrate group on the other silver bonds via two nitrate O atoms; one silver cation therefore has a coordination number of three whereas the second has a coordination number of four. One of the quinoxaline ligands has a disordered ethyl group.