An alternative approach to hard-X-ray photoelectron spectroscopy (HAXPES) has been established. The instrumental key feature is an increase of the dimensionality of the recording scheme from 2D to 3D. A high-energy momentum microscope detects electrons with initial kinetic energies up to 8 keV with a k-resolution of 0.025 Å−1, equivalent to an angular resolution of 0.034°. A special objective lens with k-space acceptance up to 25 Å−1 allows for simultaneous full-field imaging of many Brillouin zones. Combined with time-of-flight (ToF) parallel energy recording this yields maximum parallelization. Thanks to the high brilliance (1013 hν s−1 in a spot of <20 µm diameter) of beamline P22 at PETRA III (Hamburg, Germany), the microscope set a benchmark in HAXPES recording speed, i.e. several million counts per second for core-level signals and one million for d-bands of transition metals. The concept of tomographic k-space mapping established using soft X-rays works equally well in the hard X-ray range. Sharp valence band k-patterns of Re, collected at an excitation energy of 6 keV, correspond to direct transitions to the 28th repeated Brillouin zone. Measured total energy resolutions (photon bandwidth plus ToF-resolution) are 62 meV and 180 meV FWHM at 5.977 keV for monochromator crystals Si(333) and Si(311) and 450 meV at 4.0 keV for Si(111). Hard X-ray photoelectron diffraction (hXPD) patterns with rich fine structure are recorded within minutes. The short photoelectron wavelength (10% of the interatomic distance) `amplifies' phase differences, making full-field hXPD a sensitive structural tool.

Calibration of area detectors from powder diffraction standards is widely used at synchrotron beamlines. From a single diffraction image, it is not possible to determine both the sample-to-detector distance and the wavelength, but, with images taken from multiple positions along the beam direction and where the relative displacement is known, the sample-to-detector distance and wavelength can both be determined with good precision. An example calibration using the GSAS-II software package is presented.

Multilayer monochromator devices are commonly used at (imaging) beamlines of synchrotron facilities to shape the X-ray beam to relatively small bandwidth and high intensity. However, stripe artefacts are often observed and can deteriorate the image quality. Although the intensity distribution of these artefacts has been described in the literature, their spectral distribution is currently unknown. To assess the spatio-spectral properties of the monochromated X-ray beam, the direct beam has been measured for the first time using a hyperspectral X-ray detector. The results show a large number of spectral features with different spatial distributions for a [Ru, B4C] strip monochromator, associated primarily with the higher-order harmonics of the undulator and monochromator. It is found that their relative contributions are sufficiently low to avoid an influence on the imaging data. The [V, B4C] strip suppresses these high-order harmonics even more than the former, yet at the cost of reduced efficiency.

Detection of heavy elements, such as metals, in macromolecular crystallography (MX) samples by X-ray fluorescence is a function traditionally covered at synchrotron MX beamlines by silicon drift detectors, which cannot be used at X-ray free-electron lasers because of the very short duration of the X-ray pulses. Here it is shown that the hybrid pixel charge-integrating detector JUNGFRAU can fulfill this function when operating in a low-flux regime. The feasibility of precise position determination of micrometre-sized metal marks is also demonstrated, to be used as fiducials for offline prelocation in serial crystallography experiments, based on the specific fluorescence signal measured with JUNGFRAU, both at the synchrotron and at SwissFEL. Finally, the measurement of elemental absorption edges at a synchrotron beamline using JUNGFRAU is also demonstrated.

The time evolution of the electron density and the resulting time dependence of the X-ray polarizability of a crystal irradiated by highly intense XFEL femtosecond pulses is investigated theoretically. Rate equations for bound electrons and the Boltzmann equation for the unbound electron gas are used in calculations.

Melting of the semicrystalline structure of native tapioca starch granules is correlated to solution viscosity for elucidating gelatinization and gelation processes.

It has been revealed that in cylindrical nano-confinement, the hydrogen-bonding direction of nylon-12 crystals in the rod could self-assemble to be parallel to the long axis of the rod. The dominant growth direction and hydrogen-bonding direction of the γ-form crystal in the long axis of the rod has been revealed by TEM–SAED and WAXD.

Mammalian Munc18 proteins are essential for membrane fusion and human health. Here, we review the literature describing structural and in vitro data, and identify a possible explanation for the conflicting functional roles that have been reported.

A review of recent and ongoing development and results within the field of biological solution small-angle X-ray scattering (BioSAXS), with a focus on the increasing complexity of biological samples, data collection and data evaluation strategies.

A modulation wave approach is used to interpret the coupled longer range as well as truly short range order hidden in the highly structured diffuse intensity distributions of three representative such systems. The longer range as well as the truly short range order simultaneously encoded in such highly structured diffuse intensity distributions is highlighted.

Isle of Mull earthquake compared to low-flying jet  BBC News

Viewpoint: UK government should pump money into computers for science  Science Business

Tsunami warning: Britain could be hit by 30m wave - Professor warns of hazards to Britain  Express.co.uk

Climate change: Cardiff study says ground-water could heat homes  BBC News

The transmembrane intracellular lectin ER–Golgi intermediate compartment protein 53 (ERGIC-53) and the soluble EF-hand multiple coagulation factor deficiency protein 2 (MCFD2) form a complex that functions as a cargo receptor, trafficking various glycoproteins between the endoplasmic reticulum (ER) and the Golgi apparatus. It has been demonstrated that the carbohydrate-recognition domain (CRD) of ERGIC-53 (ERGIC-53CRD) interacts with N-linked glycans on cargo glycoproteins, whereas MCFD2 recognizes polypeptide segments of cargo glycoproteins. Crystal structures of ERGIC-53CRD complexed with MCFD2 and mannosyl oligosaccharides have revealed protein–protein and protein–sugar binding modes. In contrast, the polypeptide-recognition mechanism of MCFD2 remains largely unknown. Here, a 1.60 Å resolution crystal structure of the ERGIC-53CRD–MCFD2 complex is reported, along with three other crystal forms. Comparison of these structures with those previously reported reveal that MCFD2, but not ERGIC-53–CRD, exhibits significant conformational plasticity that may be relevant to its accommodation of various polypeptide ligands.

A novel monoclinic phase of human insulin co-crystallized with m-cresol was structurally characterized by means of powder and single-crystal X-ray diffraction.

A new scaling program is presented with new features to support multi-sweep workflows and analysis within the DIALS software package.

From the perspective of a young(ish) structural biologist who currently specialises in macromolecular X-ray crystallography, are the best years of crystallography over? Some evidence and hopefully thought-provoking analysis is presented here on the subject.

The asymmetric unit of the title MOF, [Zn5(C14H5NO10S2)2(OH)2(H2O)10]n comprises three ZnII atoms, one of which is located on a centre of inversion, a tetra-negative carboxyl­ate ligand, one μ3-hydroxide and five water mol­ecules, each of which is coordinated. The ZnII atom, lying on a centre of inversion, is coordinated by trans sulfoxide-O atoms and four water mol­ecules in an octa­hedral geometry. Another ZnII atom is coordinated by two carboxyl­ate-O atoms, one hy­droxy-O, one sulfoxide-O and a water-O atom to define a distorted trigonal–bipyramidal geometry; a close Zn⋯O(carboxyl­ate) inter­action derived from an asymmetrically coordinating ligand (Zn—O = 1.95 and 3.07 Å) suggests a 5 + 1 coordination geometry. The third ZnII atom is coordinated in an octa­hedral fashion by two hy­droxy-O atoms, one carboxyl­ate-O, one sulfoxide-O and two water-O atoms, the latter being mutually cis. In all, the carboxyl­ate ligand binds six ZnII ions leading to a three-dimensional architecture. In the crystal, all acidic donors form hydrogen bonds to oxygen acceptors to contribute to the stability of the three-dimensional architecture.

The structure of the title compound, C24H26S2, an example of a pincer ligand with an SCS-chelation motif, illustrates the steric effects of the methyl groups in the thio­phenyl rings at the 2- and 6-positions, forcing a dissimilar spatial orientation of the thio­phenyl rings relative to the central aryl group [dihedral angles = 33.58 (7) and 40.49 (7)°]. In the crystal, weak S⋯S contacts [3.4009 (7) Å] link the mol­ecules into inversion dimers.

The title compound, C4H9N5O2+·SO42−·H2O, is the monohydrate of the commercially available compound `C4H7N5O·H2SO4·xH2O'. It is obtained by reprecipitation of C4H7N5O·H2SO4·xH2O from dilute sodium hydroxide solution with dilute sulfuric acid. The crystal structure of anhydrous 2,4,5-tri­amino-1,6-di­hydro­pyrimidin-6-one sulfate is known, although called by the authors 5-amminium-6-amino-isocytosinium sulfate [Bieri et al. (1993). Private communication (refcode HACDEU). CCDC, Cambridge, England]. In the structure, the sulfate group is deprotonated, whereas one of the amino groups is protonated (R2C—NH3+) and one is rearranged to a protonated imine group (R2C=NH2+). This arrangement is very similar to the known crystal structure of the anhydrate. Several tautomeric forms of the investigated mol­ecule are possible, which leads to questionable proton attributions. The measured data allowed the location of all hydrogen atoms from the residual electron density. In the crystal, ions and water mol­ecules are linked into a three-dimensional network by N—H⋯O and O—H⋯O hydrogen bonds.

The asymmetric unit of the title salt, 2C12H28N+·SO42−·3H2O, contains two n-do­decyl­ammonium cations, one sulfate anion and three water mol­ecules. In the crystal, N—H⋯O hydrogen bonds link the cations and anions into layers parallel to (100). These layers are further connected through O—H⋯O hydrogen-bonding inter­actions involving the sulfate ions and the isolated water mol­ecules. The three-dimensional structure can also be considered as the superposition of thin inorganic layers of SO42− anions and thick layers of alkyl­ammonium cations perpendicular to the c axis.

The asymmetric unit of the title sulfodi­imide, C22H22N2OS, consists of two crystallographically independent mol­ecules with similar conformations The environment around each sulfur atom is a slightly distorted tetra­hedron with two S=N bonds and two S—C bonds. The S= N(m-methyl­benzo­yl) and S=N(NEt) bond lengths are 1.584 (3) and 1.528 (2) Å, respectively, for one mol­ecule, and 1.575 (2) and 1.529 (3) Å, respectively, for the other. The dihedral angles between the two phenyl rings in the mol­ecules are 86.76 (8) and 82.49 (8)°. The N—S—N—C(m-methyl­benzo­yl) and N—S—N—C(eth­yl) torsion angles are −60.5 (2) and −50.28 (19)°, respectively, for one mol­ecule, and 62.9 (2) and 44.2 (3)°, respectively, for the other. In the crystal, each independent mol­ecule is linked to its inversion-related mol­ecule via a pair of C—H⋯O hydrogen bonds, forming a dimer.

In the title compound, C14H14ClFN2O2S, the di­hydro­pyrimidine ring adopts a shallow-boat conformation and subtends a dihedral angle of 81.91 (17)° with the phenyl ring. In the crystal, N—H⋯O, N—H⋯S and C—H⋯F hydrogen bonds and C—H⋯π inter­actions are found.

Single crystals of the title complex, [Zn(C7H5N2O4)2(C2H6OS)2] or [Zn(NBZH)2(DMSO)2], were isolated from a dimethyl sulfoxide (DMSO) solution containing [Zn(NBZH)2]·2H2O (NBZH = 3-nitro­benzo­hydroxamate anion). The asymmetric unit comprises of one O,O'-chelating NBZH anion, one O-bound DMSO ligand and one zinc(II) cation localized on an inversion centre. The three-dimensional crystal packing includes N—H⋯O and C—H⋯O hydrogen bonding, as well as O⋯H and H⋯H contacts identified by Hirshfeld isosurface analysis.

The title salt, C24H27N2OS+·BF4−, was prepared by an alkyl­ation at the amino N atom attached to the sulfur atom of the corresponding sulfodi­imide. The configuration around the sulfur atom is a slightly distorted tetra­hedral geometry with two S—N bonds and two S—C bonds. The lengths of the S—N(di­ethyl­amine) and S=N(m-methyl­benzoyl­imine) bonds are 1.619 (2) and 1.551 (2) Å, respectively. The two N—S—N—C(eth­yl) and the N—S—N—C(m-methyl­benzoyl­imine) torsion angles are −85.43 (3), 58.94 (17) and 62.03 (16)°, respectively. The dihedral angle between the two phenyl rings is 84.03 (14)°. In the crystal, C—H⋯F hydrogen bonds link the cation and anion, forming a three-dimensional network.

In the title sulfanilamide derivative, C15H13NO2S, which shows significant activity against Staphylococcus aureus and Escherichia coli, the dihedral angle between the planes of the aromatic rings is 62.15 (19)° and the four-coordinate S atom adopts an almost ideal tetra­hedral geometry. In the crystal, N—H⋯O and C—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network.

The title complex, [Os3(C2H4N)H(CO)10] or [Os3(CO)10(μ-H)(μ-HN=C—CH3-1κN:2κC)], was synthesized in 41.6% yield by reactions between Os3(CO)11(CH3CN) and 2,4,6-tri­methyl­hexa­hydro-1,3,5-triazine. The central osmium triangle has two OsI atoms bridged by a hydride ligand and a μ-HN= C—CH3-1κN:2κC triazine fragment. Three CO ligands complete the coordination sphere around each OsI atom, while the remaining Os0 atom has four CO ligands. Each Os atom exhibits a pseudo-octa­hedral coordination environment, discounting the bridging Os—Os bond.

The title compound, [Bi(C9H6NS2)3], was prepared by reacting BiCl3 and 2-mercapto-4-phenyl­thia­zole (LH) at room temperature in a stoichiometric ratio of 1:4. The mol­ecular structure reveals a slightly distorted square-pyramidal environment around the BiIII atom. Two of the three monoanionic ligands L− coordinate in an N,S-bidentate mode, while one shows a monodentate mode through an S atom. There are no significant inter­molecular inter­actions present in the crystal.

The structure of the title salt, C6H10N22+·2C7H7O3S−, consists of a unique benzene-1,2-diaminium dication charge balanced by a pair of crystallographically independent 4-methyl­benzene-1-sulfonate anions. The cations and anions are inter­linked by several N—H⋯O hydrogen bonds.

The structure of the title compound, H3O+·C2F6NO4S2−·C12H24O6 or [H3O+·C12H24O6][N(SO2CF3)2−], which is an ionic liquid with a melting point of 341–343 K, has been determined at 113 K. The asymmetric unit consists of two crystallographically independent 18-crown-6 mol­ecules, two hydro­nium ions and two bis­(tri­fluoro­methane­sulfon­yl)amide anions; each 18-crown-6 mol­ecule complexes with a hydro­nium ion. In one 18-crown-6 mol­ecule, a part of the ring exhibits conformational disorder over two sets of sites with an occupancy ratio of 0.533 (13):0.467 (13). One hydro­nium ion is complexed with the ordered 18-crown-6 mol­ecule via O—H⋯O hydrogen bonds with H2OH⋯OC distances of 1.90 (6)–2.19 (7) Å, and the other hydro­nium ion with the disordered crown mol­ecule with distances of 1.85 (6)–2.36 (6) Å. The hydro­nium ions are also linked to the anions via O—H⋯F hydrogen bonds. The crystal studied was found to be a racemic twin with a component ratio of 0.55 (13):0.45 (13).

The title compound, C21H39NS2, crystallizes with two mol­ecules in the asymmetric unit, both having a linear 18-carbon alkyl chain bound through a thio­ether group. No π–π stacking or hydrogen bonding is observed. The orientation of the alkyl chains facilitates inter­molecular inter­actions between te chains. The structure is metrically ortho­rhom­bic but crystallizes in the monoclinic space group P21 and was found to be twinned by pseudomerohedry (emulating ortho­rhom­bic symmetry) and by inversion. The twin factions refined to 0.37 (4), 0.13 (4), 0.31 (5), and 0.19 (4).

The title compound, C11H10N2O2S2, crystallizes with one complete mol­ecule in the asymmetric unit. In the crystal, weak hydrogen bonding is observed between the N-oxide moieties and several C—H units.

In the extended structure of the title mol­ecular salt, C6H9N2+·C7H7O3S−, the cations and anions are linked by N—H⋯O hydrogen bonds to generate [010] chains.

The title salt, (PMIM)2[Ni(P2S8)2] (PMIM = 3-methyl-1-propyl-1H-imidazol-3-ium, C7H13N2+), consists of a nickel–thio­phosphate anion charge-balanced by a pair of crystallographically independent PMIM cations. It crystallizes in the monoclinic space group P21/n. The structure exhibits the known [Ni(P2S8)2]2− anion with two unique imidazolium cations in the asymmetric unit. Whereas one PMIM cation is well ordered, the other is disordered over two orientations with refined occupancies of 0.798 (2) and 0.202 (2). The salt was prepared directly from the elements in the ionic liquid [PMIM]CF3SO3. Whereas one of the PMIM cations is well behaved (it does not exhibit disorder even in the propyl side chain), the other is found in two overlapping positions. The refined occupancies for the two orientations are roughly 80:20. Here, too, there appears to be little disorder in the propyl arm.

Crystals of the dimethyl sulfoxide (DMSO) solvate of [1–9-NαC]-linusorb B3 (Cyclo­linopeptide A; CLP-A; C57H84N9O9·C2H6OS), a cyclic polypeptide were obtained following peptide extraction and purification from flaxseed oil. There are four intramolecular N—H⋯O hydrogen bonds. In the crystal, the mol­ecules are linked in chains along the a axis by N—H⋯O hydrogen bonds. Each DMSO O atom accepts a hydrogen bond from an NH group at the Phe6 location in the CLP-A mol­ecule.

In the title compound, C14H11ClN2O2S, the dihedral angle between the pyrrolo­[1,2-c]pyrimidine ring system (r.m.s. deviation = 0.008 Å) and the benzene ring is 80.2 (9)°. In the crystal, inversion dimers linked by pairs of C—H⋯O inter­actions generate R22(16) loops. Several aromatic π–π stacking inter­actions between the pyrrolo­[1,2-c]pyrimidine rings, as well as separately between the pyrrolo and pyrimidine groups [shortest centroid–centroid separation = 3.5758 (14) Å], help to consolidate the packing.

The title hepta­nuclear alkoxido(oxido)vanadium(V) oxide cluster complex, [V7(C10H19O)O17(C18H24N2)3]·CH3CN, was obtained by the reaction of [V8O20(C18H24N2)4] with 4-tert-butyl­cyclo­hexa­nol (mixture of cis and trans) in a mixed CHCl3/CH3CN solvent. The complex has a V7O18N6 core with approximately Cs symmetry, which is composed of two VO4 tetra­hedra, two VO6 octa­hedra and three VO4N2 octa­hedra. In the crystal, these complexes are linked together by weak inter­molecular C—H⋯O hydrogen bonds between the 4,4'-di-tert-butyl-2,2'-bi­pyridine ligand and the V7O18N6 core, forming a one-dimensional network along the c-axis direction. Besides the complex, the asymmetric unit contains one CH3CN solvent mol­ecule. The contribution of other disordered solvent mol­ecules to the scattering was removed using the SQUEEZE option in PLATON [Spek (2015). Acta Cryst. C71, 9–18]. The unknown solvent mol­ecules are not considered in the chemical formula and other crystal data.

This work presents the synthesis and structural characterization of [4-(1H-benzo[d]imidazol-2-yl)phen­oxy]phthalo­nitrile, a phthalo­nitrile derivative carrying a benzimidazole moiety. The compound crystallizes as its dimethyl sulfoxide monosolvate, C21H12N4O·(CH3)2SO. The dihedral angle between the two fused rings in the heterocyclic ring system is 2.11 (1)°, while the phenyl ring attached to the imidazole moiety is inclined by 20.7 (1)° to the latter. In the crystal structure, adjacent mol­ecules are connected by pairs of weak inter­molecular C—H⋯N hydrogen bonds into inversion dimers. N—H⋯O and C—H⋯O hydrogen bonds with R21(7) graph-set motifs are also formed between the organic mol­ecule and the disordered dimethyl sulfoxide solvent [occupancy ratio of 0.623 (5):0.377 (5) for the two sites of the sulfur atom]. Hirshfeld surface analysis and fingerprint plots were used to investigate the inter­molecular inter­actions in the crystalline state.

The title compound, C15H13BrO2S, comprises three different substituents bound to a central (and chiral) methine-C atom, i.e. (4-bromo­phen­yl)sulfanyl, benzaldehyde and meth­oxy residues: crystal symmetry generates a racemic mixture. A twist in the mol­ecule is evident about the methine-C—C(carbon­yl) bond as evidenced by the O—C—C—O torsion angle of −20.8 (7)°. The dihedral angle between the bromo­benzene and phenyl rings is 43.2 (2)°, with the former disposed to lie over the oxygen atoms. The most prominent feature of the packing is the formation of helical supra­molecular chains as a result of methyl- and methine-C—H⋯O(carbon­yl) inter­actions. The chains assemble into a three-dimensional architecture without directional inter­actions between them. The nature of the weak points of contacts has been probed by a combination of Hirshfeld surface analysis, non-covalent inter­action plots and inter­action energy calculations. These point to the importance of weaker H⋯H and C—H⋯C inter­actions in the consolidation of the structure.

The synthesis and crystal structures of a series of 6-aryl­fuvlenes (fulvene is 5-methyl­idene­cyclo­penta-1,3-diene) with varying methyl­ation patterns on the 6-phenyl substituent are reported, namely 6-(3-methyl­phen­yl)-1,3-di­phenyl­fulvene (C25H20), 6-(4-methyl­phen­yl)-1,3-di­phenyl­fulvene (C25H20), 6-mesityl-3-di­phenyl­fulvene (C27H24) and 6-(2,3,4,5,6-penta­methyl­phen­yl)-1,3-di­phenyl­fulvene (C29H28). The bond lengths are typical of those observed in related fulvenes. A network of C—H⋯π ring inter­actions consolidates the packing in each structure.

The title binuclear CoIII complex, [Co2(C9H8BrNOS)2(C18H16Br2N2O2S2)]·C3H7NO, with a Schiff base ligand formed in situ from cyste­amine (2-amino­ethane­thiol) and 5-bromo­salicyl­aldehyde crystallizes in the space group P21. It was found that during the synthesis the ligand undergoes spontaneous oxidation, forming the new ligand H2L' having an S—S bond. Thus, the asymmetric unit consists of one Co2(L)2(L') mol­ecule and one DMF solvent mol­ecule. Each CoIII ion has a slightly distorted octa­hedral S2N2O2 coordination geometry. In the crystal, the components are linked into a three-dimensional network by several S⋯ Br, C⋯ Br, C—H⋯Br, short S⋯C (essentially shorter than the sum of the van der Waals radii for the atoms involved) contacts as well by weak C—H⋯O hydrogen bonds. The crystal studied was refined as an inversion twin.

In the title compound, the asymmetric unit comprises an N,N,N-trimethyl-1-(4-vinyl­phen­yl)methanaminium cation and a 4-vinyl­benzene­sulfonate anion, C12H18N+·C8H7O3S−. The salt has a polymerizable vinyl group attached to both the cation and the anion. The methanaminium and vinyl substituents on the benzene ring of the cation subtend angles of 86.6 (3) and 10.5 (9)° to the ring plane, while the anion is planar excluding the sulfonate O atoms. The vinyl substituent on the benzene ring of the cation is disordered over two sites with a refined occupancy ratio of 0.542 (11):0.458 (11). In the crystal, C—H⋯O hydrogen bonds dominate the packing and combine with a C—H⋯π(ring) contact to stack the cations and anions along the a-axis direction. Hirshfeld surface analysis of the salt and of the individual cation and anion components is also reported.

The title compound, C22H22N2O4S2, was synthesized by the reaction of 1,4,5,8-naphthalene­tetra­carb­oxy­lic dianhydride with 3-(methyl­sulfan­yl)propyl­amine. The whole mol­ecule is generated by an inversion operation of the asymmetric unit. This mol­ecule has an anti form with the terminal methyl­thio­propyl groups above and below the aromatic di­imide plane, where four intra­molecular C—H⋯O and C—H⋯S hydrogen bonds are present and the O⋯H⋯S angle is 100.8°. DFT calculations revealed slight differences between the solid state and gas phase structures. In the crystal, C—H⋯O and C—H⋯S hydrogen bonds link the mol­ecules into chains along the [2overline20] direction. adjacent chains are inter­connected by π–π inter­actions, forming a two-dimensional network parallel to the (001) plane. Each two-dimensional layer is further packed in an ABAB sequence along the c-axis direction. Hirshfeld surface analysis shows that van der Waals inter­actions make important contributions to the inter­molecular contacts. The most important contacts found in the Hirshfeld surface analysis are H⋯H (44.2%), H⋯O/O⋯H (18.2%), H⋯C/C⋯H (14.4%), and H⋯S/S⋯H (10.2%).

The structures of two isomers of the title compound, [RuCl2(C14H12N4)(C2H6OS)2], 2 and 3, are reported. Isomers 2 and 3 are produced by reaction of the pyridyl­triazole ligand 1-benzyl-4-(pyridin-2-yl)-1H-1,2,3-triazole (bpt) (1) with fac-[RuCl2(DMSO-S)3(DMSO-O)]. Reaction in acetone produces ca 95% 2, which is the OC-6-14 isomer, with cis DMSO and trans chlorido ligands, and 5% 3 (the OC-6-32 isomer, with cis DMSO and cis chlorido ligands, and the pyridyl moiety of bpt trans to DMSO). Reaction in refluxing toluene initially forms 2, which slowly isomerizes to 3.

In the crystal structure of the isostructural title compounds, namely {2,6-bis­[(di-tert-butyl­phosphan­yl)­oxy]-4-hy­droxy­phen­yl}chlorido­palladium(II), [Pd(C22H39O3P2)Cl], 1, and {2,6-bis­[(di-tert-butyl­phosphan­yl)­oxy]-4-hy­droxy­phen­yl}chlorido­platinum(II), [Pt(C22H39O3P2)Cl], 2, the metal centres are coordinated in a distorted square-planar fashion by the POCOP pincer fragment and the chloride ligand. Both complexes form strong hydrogen-bonded chain structures through an inter­action of the OH group in the 4-position of the aromatic POCOP backbone with the halide ligand.

The title compound, hexa­kis­(2-methyl-1H-imidazol-3-ium) hepta­molybdate 2-methyl-1H-imidazole disolvate dihydrate, (C4H7N2)6[Mo7O24]·2C4H6N2·2H2O, was prepared from 2-methyl­imidazole and ammonium hepta­molybdate tetra­hydrate in acid solution. The [Mo7O24]6− hepta­molybdate cluster anion is accompanied by six protonated (C4H7N2)+ 2-methyl­imidazolium cations, two neutral C4H6N2 2-methyl­imidazole mol­ecules and two water mol­ecules of crystallization. The cluster consists of seven distorted MoO6 octa­hedra sharing edges or vertices. In the crystal, the components are linked by N—H⋯N, N—H⋯O, O—H⋯O, N—H⋯(O,O) and O—H⋯(O,O) hydrogen bonds, generating a three-dimensional network. Weak C—H⋯O inter­actions consolidate the packing.

The title mol­ecule crystallizes as a di­methyl­formamide monosolvate, C19H14N2O6S2·C3H7NO. The mol­ecule was expected to adopt mirror symmetry but slightly different conformational characteristics of the condensed benzo­thia­zine ring lead to point group symmetry 1. In the crystal, mol­ecules form two types of stacking dimers with distances of 3.464 (2) Å and 3.528 (2) Å between π-systems. As a result, columns extending parallel to [100] are formed, which are connected to inter­mediate di­methyl­formamide solvent mol­ecules by C—H⋯O inter­actions.

This study is an investigation into the crystal structure of the biologically active drug mol­ecule riluzole [RZ, 6-(tri­fluoro­meth­oxy)-1,3-benzo­thia­zol-2-amine], C8H5F3N2OS, and its derivative, the riluzolium chloride salt [RZHCl, 2-amino-6-(tri­fluoro­meth­oxy)-1,3-benzo­thia­zol-3-ium chloride], C8H6F3N2OS+·Cl−. In spite of repeated efforts to crystallize the drug, its crystal structure has not been reported to date, hence the current study provides a method for obtaining crystals of both riluzole and its corresponding salt, riluzolium hydro­chloride. The salt was obtained by grinding HCl with the drug and crystallizing the obtained solid from di­chloro­methane. The crystals of riluzole were obtained in the presence of l-glutamic acid and d-glutamic acid in separate experiments. In the crystal structure of RZHCl, the –OCF3 moiety is perpendicular to the mol­ecular plane containing the riluzolium ion, as can be seen by the torsion angle of 107.4 (3)°. In the case of riluzole, the torsion angles of the four different mol­ecules in the asymmetric unit show that in three cases the tri­fluoro­meth­oxy group is perpendicular to the riluzole mol­ecular plane and only in one mol­ecule does the –OCF3 group lie in the same mol­ecular plane. The crystal structure of riluzole primarily consists of strong N—H⋯N hydrogen bonds along with weak C—H⋯F, C—H⋯S, F⋯F, C⋯C and C⋯S inter­actions, while that of its salt is stabilized by strong [N—H]+⋯Cl− and weak C—H⋯Cl−, N—H⋯S, C—H⋯F, C⋯C, S⋯N and S⋯Cl− inter­actions.