forthcoming articles

The following articles are a selection of those recently accepted for publication in IUCr journals.

IUCrJ
Accepted 9 January 2017

The mechanism behind the selection of two different cleavage sites in NAG-NAM polymer

The crystal structure of autolysin E, an N-acetylglucosaminidase from S. aureus, reveals the structural basis of the selection mechanism of muramidases and glucosaminidases for docking the two chemically equivalent yet by sequence distinct β-glycosidic bonds in NAG-NAM polymers.

Accepted 6 January 2017

Incommensurate atomic density waves in the high-pressure IVb phase of barium

Using single-crystal synchrotron radiation X-ray experiments, the host–guest structure of the Ba IVb high-pressure phase has been solved for the first time. The proposed systematic analysis of possible host–guest structure models shows that the structure belongs to the incommensurately modulated type. This model reveals an atomic density wave and its pressure-dependent evolution between 16.5 and 19.6 GPa.

Accepted 29 December 2016

In-cell NMR: a topical review

In-cell NMR has emerged in the past decade as a unique approach to obtain structural and functional information on biological macromolecules within living cells at atomic resolution. In this review, the major advancements of in-cell NMR are discussed, with a special focus on the recent developments and applications in eukaryotic and mammalian cells.

Accepted 27 December 2016

Advances in mass-spectrometric strategies to study receptor tyrosine kinases

This review discusses advances in mass spectrometry-based strategies to investigate receptor tyrosine kinase signalling networks and activation dynamics.

Accepted 20 December 2016

Atom interaction propensities of oxygenated chemical functions in crystal packings

Intermolecular crystal contacts formed by different oxygen atom types are investigated.

Accepted 29 November 2016

Metal–organic frameworks for H2 and CH4 storage: insights on the pore geometry–sorption energetics relationship

Controlling the MOF pore geometry, size and functionality is of prime importance for the effective and selective gas adsorption. Gas adsorption studies on ultra-microporous MOFs were conducted to gain insight on the pore geometry–sorption energetics relationship.
Journal logoActa Crystallographica Section A
Acta Crystallographica
Section A
FOUNDATIONS AND ADVANCES

Accepted 22 December 2016

A theoretical investigation of orientation relationships and transformation strains in steels

A unified approach to derive transformation strains and orientation relationship models in steels is presented. This unified approach is used to derive the Nishiyama-Wassermann, Kurdjumov-Sachs and other models and extend them naturally to the situation of a tetragonal \alpha^\prime-phase.

Accepted 7 December 2016

B7 as a supergroup of crystal and quasicrystal symmetries

[This paper describes the] Practical generation of all Bravais as well as quasicrystal symmetries from a finite group.

Accepted 1 December 2016

Hyperbolic crystallography of two-periodic surfaces and associated structures

The intrinsic, hyperbolic crystallography of the two-periodic, genus-two HCB and SQL surfaces is presented. All discrete groups containing the translations of the Euclidean embeddings of these surfaces are derived and examples of applications are given.

Accepted 28 November 2016

Dynamic quantum crystallography: lattice-dynamical models refined against diffraction data. II. Applications to L-alanine, naphthalene and xylitol

The performance of a lattice-dynamical model refined against elastic Bragg scattering data is tested on L-alanine, naphthalene and xylitol.

Accepted 24 November 2016

Crystallography: A Very Short Introduction


Accepted 22 November 2016

Asymmetry in serial femtosecond crystallography data

Distribution analysis of intensity observations in serial femtosecond crystallography data processing helps to separate Bragg reflections from the background detector response.
Journal logoActa Crystallographica Section B
Acta Crystallographica
Section B
STRUCTURAL SCIENCE, CRYSTAL ENGINEERING AND MATERIALS

Accepted 2 December 2016

Theoretical insights into the π-hole interactions in the complexes containing tri­phosphorus hydride (P3H3) and its derivatives

The π-hole of triphosphorus hydride (P3H3) and its derivatives Z3X3 (Z = P, As; X = H, F, Cl, Br) were discovered. The relative π-hole interactions belong to the closed-shell noncovalent interaction and the stabilization mainly results from electrostatic energy.

Accepted 2 December 2016

A revised interpretation of the structure of (NH4)2Ge7O15 in the light of the Extended Zintl–Klemm Concept

The Extended Zint–Klemm Concept accounts for the tetrahedral and octahedral coordination of Ge atoms in (NH42Ge7O15

Accepted 1 December 2016

Formation of co-racemic uranyl chromate constructed from chiral layers of different topology

A unique uranyl-based structural architecture formed by chiral layers of different topology is described. Layer pairs of different topology can be considered as racemic pairs and the whole structure is a co-racemate built by a combination of two racemates.

Accepted 28 November 2016

Structures and thermal stability of the α-LiNH4SO4 polytypes doped with Er3+ and Yb3+

We present new results about the polymorphism of LiNH4SO4. Two new α-polytypes have been obtained, thanks to doping effects. The thermal stability of the α-modification is clarified and the coexistence of α- and β-polytypes and the mechanism of the α → β phase transition is proposed.

Accepted 23 November 2016

Synchrotron X-ray diffuse scattering from a stable polymorphic material: terephthalic acid, C8H6O4

A model for the X-ray diffuse scattering from terephthalic acid (C8H6O4) is presented, and used to explore the sensitivity of diffuse scattering to polymorphic interconversion, and to demonstrate the relative ease with which the harmonic (`thermal') component of the diffuse scattering can be modelled.

Accepted 16 November 2016

Neutron and X-ray investigations of the Jahn–Teller switch in partially deuterated ammonium copper tutton salt, (NH4)2[Cu(H2O)6](SO4)2

Pressure, temperature and deuteration-dependent phase transition in the ammonium copper salt, (NH4)2[Cu(H2O)6](SO4)2, was studied using neutron and X-ray diffraction on single crystal and powder samples.

Accepted 14 November 2016

Isothermal equation of state and high-pressure phase transitions of synthetic meridianiite (MgSO4·11D2O) determined by neutron powder diffraction and quasielastic neutron spectroscopy

We report high-pressure neutron powder diffraction measurements of the most hydrated phase in the MgSO4–H2O system, magnesium sulfate undecahydrate, including an analysis of the elastic strain tensor and observations concerning phase changes that occur at high pressure.

Accepted 14 November 2016

Structure, thermal expansion and incompressibility of MgSO4·9H2O, its relationship to meridianiite (MgSO4·11H2O) and possible natural occurrences

We have employed neutron and X-ray powder diffraction and density functional theory calculations to determine the structure and thermoelastic properties of a new hydrate in the MgSO4–H2O binary system, magnesium sulfate enneahydrate. We show that this 9-hydrate could occur naturally in certain hypersaline lakes on Earth and indicate where it may be formed as a more persistent mineral elsewhere in the solar system.

Accepted 14 November 2016

Crystal structure prediction by ionic network analysis: the example of (pTX)-structure relationships in olivines

A predictive method for the unit-cell parameters and atomic coordinates of ionic crystals is described. It is based on crystal structures known at systematically varying values of pressure, temperature or chemical composition, and applied to olivines

Accepted 14 November 2016

An unusual case of OD-allotwinning: 9,9′-(2,5-di­bromo-1,4-phenylene)bis­[9H-carbazole]

The title compound crystallizes as allotwins made up of two OD-polytypes with a maximum degree of order.

more ...
Journal logoActa Crystallographica Section C
Acta Crystallographica
Section C
STRUCTURAL CHEMISTRY

Accepted 13 January 2017

Ab initio crystal structure prediction of magnesium (poly)sulfides and calculation of their NMR parameters

Experimentally observed crystalline forms of MgS were successfully predicted from first principles and an inter­esting hypothetical structure of MgS2 was identified. For all these forms, 25Mg NMR parameters (chemical shifts and quadrupolar coupling constants) were calculated.

Accepted 12 January 2017

Structure of a penta­manganese(II)–phenoxide cluster with a central five-coordinate oxide: MnII5(μ-OPh)63-OPh)2(μ5-O)(Py)6·Py (Py is pyridine)

The structure of a manganese cluster containing an unusual central trigonal bipyramidal oxide is described.

Accepted 12 January 2017

Structure of salts of lithium chloride and lithium hexa­fluoro­phosphate as solvates with pyridine and vinyl­pyridine and structural comparisons: (C5H5N)LiPF6, [p-(CH2=CH)C5H5N]LiPF6, [(C5H5N)LiCl]n, and [p-(CH2=CH)C5H5N]2Li(μ-Cl)2Li[p-(CH2=CH)C5H5N]2

Dissolution of LiCl or LiPF6 into pyridine or vinyl­pyridine and slow vapor diffusion of this solution with diethyl ether gives solvates of the lithium salts coordinated by pyridine ligands. In the case of the hexa­fluorophosphate salts, the chemical species formed are similar, namely binary salts with hexa­fluoro­phosphate counter-ions. In contrast, the solvates with LiCl are structurally dissimilar, with one forming a one-dimensional ionic polymer of fused LiCl rhombs and the other crystallizing as an isolated mol­ecular unit with a complex array of van der Waals inter­actions of neighboring mol­ecules.

Accepted 9 January 2017

The ambient hydration of the aluminophosphate JDF-2 to AlPO-53(A): insights from NMR crystallography

Using multinuclear solid-state NMR spectroscopy and first-principles DFT calculations, we examine the slow ambient hydration of the AEN-type aluminophosphate, JDF-2, to AlPO-53(A). We propose a modified version of the published structure of AlPO-53(A), with reorientation of the methyl­ammonium cations and partial occupancy of the water sites.

Accepted 6 December 2016

Structure determination of a partially ordered layered silicate material with an NMR crystallography approach

A structural model for the cetyltri­methyl­ammonium surfactant-templated layered silicate material, which lacks full three-dimensional crystallinity, is reported based an NMR crystallography approach which combines structural information obtained from powder X-ray diffraction and solid-state nuclear magnetic resonance spectroscopy.

Accepted 2 December 2016

Insight into the local environment of magnesium and calcium in low-coordination-number organo-complexes using 25Mg and 43Ca solid-state NMR: a DFT study

DFT calculations of 25Mg and 43Ca NMR parameters were performed on the crystal structures of organomagnesium and organocalcium complexes involving low coordination numbers and N-bearing ligands. It is shown how these spectroscopies may be used for these systems for NMR crystallography approaches.

Accepted 8 November 2016

NMR crystallography to probe the breathing effect of the MIL-53(Al) metal–organic framework using solid-state NMR measurements of 13C–27Al distances

We show how 13C–27Al solid-state NMR experiments distinguish between the large and narrow pore structures of MIL-53(Al). These experiments also prove the rigidity of these structures and provide an estimate of the average distance between the free ligand and the framework in the as-synthesized MIL-53(Al) material.

Accepted 24 October 2016

Inter­molecular inter­actions in AST zeolites through 14N NMR and DFT calculations

The reinvestigation of silica AST zeolite by 14N NMR and DFT calculations allows the highlighting of inter­molecular inter­actions involving the tetra­methyl­ammonium cations and fluoride anions (hydrogen and tetrel bonds) that strengthen the stability of the whole structure.

Accepted 4 October 2016

Solid-state NMR and short-range order in crystalline oxides and silicates: a new tool in paramagnetic resonances

In many oxide and silicate materials containing paramagnetic components at the hundreds of ppm to many percent level, high-resolution solid-state NMR spectra can provide important new types of information about short-range cation order/disorder, through often-large effects of unpaired electron spins on nuclear spins.
Journal logoActa Crystallographica Section D
Acta Crystallographica
Section D
STRUCTURAL BIOLOGY

Accepted 13 January 2017

The use of small-molecule structures to complement protein–ligand crystal structures in drug discovery

Small-molecule crystal structures are of tremendous value in understanding protein–ligand complexes, both individually and as a collection.

Accepted 13 January 2017

Dissecting random and systematic differences between noisy composite data sets

A multidimensional scaling analysis of the pairwise correlation coefficients is presented which positions datasets in a sphere with radius one of an abstract, low-dimensional space at radii inversely proportional to their levels of random error, and at spherical angles related to their mutual systematic differences. This dimensionality reduction can not only be used for classification purposes, but also to derive dataset relations on a continuous scale.

Accepted 12 January 2017

Data mining of iron(II) and iron(III) bond valence parameters, and their relevance for macromolecular crystallography

Using all available metal-containing organic compound structures in the Cambridge Structural Database, we developed a novel data-driven method to derive bond valence R0 parameters. While confirming almost all reference literature values, we observe two distinct populations of Fe(II)-N and Fe(III)-N bonds which we interpret as low and high spin states of the coordinating iron. Based on the R0 parameters derived herein, we suggest guidelines for the modeling of iron-ligand distances in macromolecular structures.

Accepted 3 January 2017

AceDRG: a stereochemical description generator for ligands

The program AceDRG generates accurate stereochemical descriptions, and one or more conformations, of a given ligand. The program also analyses entries and extracts local environment-dependent atom types, bonds and angles from the Crystallography Open Database.

Accepted 3 January 2017

Validation and extraction of molecular-geometry information from small-molecular databases

The entries from a freely available small-molecule database, the Crystallography Open Database, have been validated and a reliable subset of molecules has been selected for the extraction of molecular-geometry information. The atom types and corresponding bond and angle classes derived from this database have been subjected to validation, the results of which are used by AceDRG in the derivation of new ligand descriptions.

Accepted 2 January 2017

Crystal structure and RNA-binding properties of an Hfq homolog from the deep-branching Aquificae: conservation of the lateral RNA-binding mode

The structure of an Hfq homolog from the deep-branching thermophilic bacterium A. aeolicus, determined to 1.5 Å resolution both in the apo form and bound to a uridine-rich RNA, reveals a conserved, pre-organized RNA-binding pocket on the lateral rim of the Hfq hexamer.

Accepted 21 December 2016

Guidelines for the successful generation of protein–ligand complex crystals

This article aims to guide efforts in protein–ligand complex crystal structure generation, with special consideration of protein-construct design, and summarizes different approaches to co-crystallization and crystal soaking. Common problems and pitfalls are highlighted.

Accepted 21 December 2016

Getting the chemistry right: protonation, tautomers and the importance of H atoms in biological chemistry

H atoms are `hard to see' in X-ray crystal structures of protein–ligand complexes. This paper discusses the problem of identifying the correct tautomeric form(s) of protein-bound ligands.

Accepted 20 December 2016

The XChemExplorer graphical workflow tool for routine or large-scale protein–ligand structure determination

XChemExplorer is a graphical workflow and data-management tool for the parallel determination of protein–ligand complexes. Its implementation, usage and application are described here.

Accepted 19 December 2016

Ligand fitting with CCP4

The process of ligand fitting with CCP4 is reviewed, including identifying ligand density in the map, ligand fitting, refinement and subsequent validation. Recent developments are discussed, and are illustrated using instructive examples demonstrating practical application.

more ...
Journal logoActa Crystallographica Section E
Acta Crystallographica
Section E
CRYSTALLOGRAPHIC COMMUNICATIONS

Accepted 17 January 2017

Crystal structure of bis­(1-ethyl­pyridinium) dioxonium hexa­cyanidoferrate(II)

The crystal structure of the title compound comprises a segregated columnar structure of cations and anions extending parallel to the b axis

Accepted 16 January 2017

Crystal structure of catena-poly[[bis­(acetato-κO)copper(II)]-bis­[μ-4-(1H-imidazol-1-yl)phenol]-κ2N3:O2O:N3]

The title compound exhibits a polymeric structure caused by long Cu⋯O inter­actions, which lead to the formation of chains parallel to [100]. In the crystal, the chains are arranged in a distorted hexa­gonal rod packing.

Accepted 16 January 2017

Crystal structure of dicesium hydrogen citrate from laboratory single-crystal and powder X-ray diffraction data and DFT comparison

The crystal structure of dicesium hydrogen citrate has been solved using laboratory X-ray single-crystal diffraction data, refined using laboratory powder data, and optimized using density functional techniques.

Accepted 16 January 2017

Crystal structure of chlorido­bis­[(1,2,5,6-η)-cyclo­octa-1,5-diene]iridium(I)

A direct synthesis of monomeric IrCl(1,5-cod)2 (1,5-cod = cyclo­octa-1,5-diene) from IrCl3·3H2O and its crystal structure are presented. The mol­ecule's shape is midway between square pyramidal and trigonal bipyramidal.

Accepted 15 January 2017

Crystal structure of trirubidium citrate monohydrate from laboratory X-ray powder diffraction data and DFT comparison

The crystal structure of trirubidium citrate monohydrate has been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques.

Accepted 15 January 2017

fac-Aceto­nitrile­tricarbon­yl(di­methyl­carbamodi­thio­ato-κ2S,S′)rhenium(I): crystal structure and Hirshfeld surface analysis

An octa­hedral fac-C3NS2 coordination geometry is found for the ReI atom in the title compound; the di­thio­carbamate ligand forms symmetric Re—S bonds. In the crystal, supra­molecular layers are formed via weak C—H⋯O inter­actions.

Accepted 12 January 2017

Crystal structure of (E)-4-Hy­droxy-6-methyl-3-{1-[2-(4-nitro­phen­yl)hydrazinyl­idene]eth­yl}-2-H-pyran-2-one

(E)-4-Hy­droxy-6-methyl-3-{1-[2-(4-nitro­phen­yl)hydrazinyl­idene]eth­yl}-2-H-pyran-2-one has been synthesized and characterized by single-crystal X-ray diffraction and by using FT–IR, 1H and 13C NMR and UV–Vis spectroscopic techniques.
Journal logoActa Crystallographica Section F
Acta Crystallographica
Section F
STRUCTURAL BIOLOGY COMMUNICATIONS

Accepted 29 December 2016

Crystallization and X-ray analysis of D-threonine aldolase from Chlamydomonas reinhardtii

Recombinant D-threonine aldolase from the green alga C. reinhardtii was purified to homogeneity and crystallized. An X-ray diffraction data set was collected to 1.85 Å resolution.

Accepted 28 December 2016

Crystal structure of the N-terminal anticodon-binding domain of the nondiscriminating aspartyl-tRNA synthetase from Helicobacter pylori

The crystal structure of the N-terminal anticodon-binding domain of the nondiscriminating aspartyl-tRNA synthetase from the human pathogen H. pylori was determined at a resolution of 2.0 Å. Two important turns (78GAGL81 and 83NPKL86), along with the conserved Pro84, are proposed to play a crucial role in the recognition of tRNAAsp and tRNAAsn.

Accepted 27 December 2016

Expression and crystallographic studies of D-glycero-β-D-manno-heptose-1-phosphate adenylyltransferase from Burkholderia pseudomallei

D-glycero-β-D-manno-Heptose-1-phosphate adenylyltransferase (HldC) from B. pseudomallei has been cloned, expressed, purified and crystallized. Synchrotron X-ray data from a selenomethionine-substituted HldC crystal were collected to 2.8 Å resolution.

Accepted 21 December 2016

Crystallization of a fungal lytic polysaccharide monooxygenase expressed from glycoengineered Pichia pastoris for X-ray and neutron diffraction

Polysaccharide monooxygenase 2 from N. crassa was expressed from a glycoengineered strain of P. pastoris. Crystals of the protein bearing modified N-linked glycans showed improved X-ray diffraction at 100 K (1.20 Å resolution) and permitted room-temperature neutron diffraction data collection to 2.12 Å resolution.
Journal logoJournal of Applied Crystallography Journal of Applied
Crystallography

Accepted 10 January 2017

Ind_X: program for indexing single-crystal diffraction patterns

A Windows console program Ind_X for indexing single-crystal diffraction patterns is presented, and the implemented indexing method is briefly described.

Accepted 6 January 2017

Crystallographic and optical study of PbHfO3 crystals

This article details the use of birefringence imaging microscopy and high-resolution x-ray diffraction for determining the symmetries of the phases in PbHfO3 between room temperature and 870 K.

Accepted 5 January 2017

Debye-Waller coefficient of heavily deformed nanocrystalline iron

Extensive deformation of an iron alloy powder increases the static disorder contribution to the thermal factor, with a ~20% increase of Debye-Waller coefficient observed both by XRD and by EXAFS. MD simulations shed light on the underlying mechanisms, confirming the major role played by the grain boundary.

Accepted 3 January 2017

Enhanced crystalline perfection and fluorescence properties of p-terphenyl single crystals grown by vertical Bridgman technique with a novel modified growth vessel

Transparent p-terphenyl single crystals were grown by vertical Bridgman technique with the original and improved double-wall growth ampoules. The enhanced crystalline perfection and fluorescence properties of the improved-ampoule-grown crystal suggest that vertical Bridgman growth method with the modified growth vessel is effective for growing high-quality bulk single crystals of low-melting-point organic materials.

Accepted 28 December 2016

Nondestructive separation of residual stress and composition gradients in thin films by angle- and energy-dispersive X-ray diffraction. I. Theoretical concepts

Four different X-ray methods are introduced which allow for depth-resolved residual stress analysis in thin films with a chemical composition gradient.

Accepted 28 December 2016

Nondestructive separation of residual stress and composition gradients in thin films by angle- and energy-dispersive X-ray diffraction. II. Experimental validation

Four different X-ray methods are introduced which allow for depth-resolved residual stress analysis in thin films with chemical composition gradient.

Accepted 23 December 2016

On the completeness of the β→ω transformation in metastable β titanium alloys

The degree of completeness of the β→ω transformation in a metastable β titanium alloy has been determined by X-ray diffraction.

Accepted 22 December 2016

Structure evolution of aluminosilicate sol and its structure-directing effect on the synthesis of NaY zeolite

This work sheds some light on the impact of SiO2/Al2O3 ratios of the sol on structure evolution, including particle size, fractal dimension and the interplay between the fractal dimension and its activity to generate NaY zeolite. The mechanisms regulating the growth behaviour of the sols during ageing are proposed.

Accepted 16 December 2016

A Bayesian approach to modeling diffraction profiles and application to ferroelectric materials

This manuscript demonstrates an entirely different numerical approach for profile modeling/fitting of diffraction peaks, Bayesian statistics combined with a stochastic sampling algorithm, which substantially increases the fidelity of information available in characterizing domain reorientation in ferroelectric materials.

Accepted 16 December 2016

Comparative study of structural phase transitions in bulk and powdered Fe–27Ga alloy by real-time neutron thermodiffractometry

High-resolution and high-intensity neutron diffraction was applied to characterize the atomic and magnetic structure and microstructure of Fe–27Ga alloy in the as-cast and powder states. Structural phase transformations occur with a noticeable difference in the as-cast and powder states of the alloy.

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Journal logoJournal of Synchrotron Radiation Journal of
Synchrotron Radiation

Accepted 4 January 2017

Nondestructive imaging of the internal micro­structure of vessels and nerve fibers in rat spinal cord using phase-contrast synchrotron radiation microtomography

In this study, firstly the phase-contrast synchrotron radiation microtomography technique has been employed for nondestructive imaging of the internal microstructure of rat spinal cord, such as white matter, gray matter, micovasculars and nerve fibers. Thus, it was confirmed that this technique has the potential to be a powerful tool for the comprehensive characterization of physiological and pathophysiological characteristics of various neurovascular and neurodegeneration diseases.

Accepted 4 January 2017

Development of new CdZnTe detectors for room-temperature high-flux radiation measurements


Accepted 4 January 2017

Computer-assisted area detector masking

A novel system for automatically masking two-dimensional area detector data is presented.

Accepted 4 January 2017

Improving the spatial and statistical accuracy in X-ray Raman scattering based direct tomography

An algorithm to simultaneously increase the spatial and statistical accuracy of X-ray Raman scattering based tomographic images is presented.

Accepted 28 December 2016

A large-solid-angle X-ray Raman scattering spectrometer at ID20 of the European Synchrotron Radiation Facility


Accepted 26 December 2016

Compact IR synchrotron beamline design

An infrared (IR) optical layout directly integrated into a synchrotron dipole chamber and compatible with multi-bend achromat lattices is proposed. This is shown to provide intense and almost aberration-free focused IR radiation beams.

Accepted 24 December 2016

Simulating and optimizing compound refractive lens-based X-ray microscopes

A comprehensive ray-transfer matrix formalism for the use and design of compound refractive lens-based X-ray microscopes is presented, including closed analytical expressions for key optical parameters. These form the basis of an optimization, which reveals that thick-lens imaging geometries are ideal in terms of spatial resolution and achromaticity.

Accepted 18 December 2016

A convolutional neural network approach to calibrating the rotation axis for X-ray computed tomography

Use of convolutional neural networks for automated calibration of rotation axes is described.

Accepted 8 December 2016

Surface EXAFS via differential electron yield

The surface-sensitive performance of extended X-ray absorption fine structure (EXAFS) spectroscopy via differential electron yield is demonstrated using a thickness-defined SiO2 (12.4 nm)/Si sample. The Si K-edge EXAFS spectrum suggests an analysis depth of approximately 4.2 nm, and the derived first nearest neighbor (Si—O) distance was 1.63 Å, which is within the reported values of SiO2.

Accepted 2 December 2016

Study on the reflectivity properties of spherically bent analyser crystals. Corrigendum


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Journal logoIUCrData
IUCrData

Accepted 16 January 2017

2,2′-[(1E,1′E)-1,2-Phenyl­enebis(aza­nylyl­idene)bis­(methanylyl­idene)]bis­(4-bromo­phenol)

The title compound has pseudo-twofold rotation symmetry, with two intra­molecular O—H⋯N hydrogen bonds forming S(6) ring motifs.

Accepted 15 January 2017

1-(3-Phenyl-1H-pyrazol-5-yl)-1,2,3,4-tetra­hydro­quinoxaline-2,3-dione

In the crystal, mol­ecules are connected by bifurcated N—H⋯(N,O) and N—H⋯(O,O) hydrogen bonds, generating (100) sheets.

Accepted 10 January 2017

(Z)-2-(4-Meth­oxy­anilino)-1,4-di­phenyl­but-2-ene-1,4-dione

In the title compound, the mean plane of the meth­oxy­phenyl ring makes dihedral angles of 51.63 (8) and 50.86 (8)° with the terminal phenyl rings.. The crystal structure features C—H⋯O hydrogen bonds.

Accepted 4 December 2016

Ethyl 3-[3-amino-4-methyl­amino-N-(pyridin-2-yl)benzamido]­propano­ate

In the crystal of the title compound, mol­ecules are linked by N—H⋯O hydrogen bonds and C—H⋯π inter­actions, forming slabs parallel to the ac plane.


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