Charge-density analysis using multipolar atom and spherical charge models: 2-methyl-1,3-cyclopent­anedione, a compound displaying a resonance-assisted hydrogen bond

The electron density of 2-methyl-1,3-cyclopentanedione was refined versus synchrotron ultra-high-resolution data using a multipolar model and a virtual and real spherical atoms model. The electrostatic properties were analyzed.

LiZn_4 − x (x = 0.825) as a (3 + 1)-dimensional modulated derivative of hexagonal close packing

The derivative from the hexagonal close packing LiZn_4 − x (x = 0.825) binary compound crystallizes in the orthorhombic superspace group Cmcm(α00)0s0.

M_mH_n(XO₄)_(m+n)/2 crystals: structure, phase transitions, hydrogen bonds, conductivity. I. K₉H₇(SO₄)₈·H₂O crystals – a new representative of the family of solid acid conductors

Diffraction studies of K₉H₇(SO₄)₈·H₂O crystals were performed using synchrotron radiation in the temperature range 293–450 K in order to reveal the structural conditionality for anomalies in physical properties.

Calcium carbonate microparticle growth controlled by a conjugate drug–copolymer and crystallization time

The influence of reaction time on the CaCO₃ microparticle growth in the presence of a conjugate drug–copolymer has been studied. The sorption capacity of composite materials is influenced by the ratio between polymorphs, and increased with the increase of calcite content and ageing time.

X-ray crystal structures of Al-doped (Y,Ca)Ba₂Cu₃O_7−y whiskers

The gradual transition from orthorhombic to tetragonal space group of Al⁺³-doped (Y,Ca)Ba₂Cu₃O_7−y (YBCO) whiskers has been studied, focusing on the relationships between structural aspects and the physical properties of these materials.

Superspace description of wagnerite-group minerals (Mg,Fe,Mn)₂(PO₄)(F,OH)

A unified superspace model, based on average triplite structure, for the description of different modulation periodicities of wagnerite and related phases

Assessing the performance of density functional theory in optimizing molecular crystal structure parameters

A computational study to assess the performance of dispersion-corrected plane-wave density functional theory to simulate reliable structural information for molecular crystal structures dominated by hydrogen bonding and dispersion interactions is reported.

Monoclinic superstructure in orthorhombic Ce₁₀W₂₂O₈₁ from transmission electron microscopy

A monoclinic superstructure occurring in a Ce₁₀W₂₂O₈₁ compound was identified by transmission electron microscopy. The partial oxidation of Ce³⁺ along with interstitial oxygen ions could explain this superstructure.

Structure refinement of the δ_1p phase in the Fe–Zn system by single-crystal X-ray diffraction combined with scanning transmission electron microscopy

The structure of the title compound has been refined by single-crystal synchrotron X-ray diffraction combined with spherical-aberration-corrected scanning transmission electron microscopy. The structure consists of iron-centred normal and disordered Zn₁₂ icosahedra, zinc-centred Zn₁₂ icosahedra, zinc-centred Zn₁₆ icosioctahedra, and dangling Zn atoms that do not constitute any polyhedra.

Average structures of the disordered β-phase of Pigment Red 170: a single-crystal X-ray diffraction study

Single-crystal X-ray diffraction of the β-phase of Pigment Red 170 reveals lines of strong diffuse scattering indicating severe layer stacking disorder. An attempt to deduce an average structure resulted in two plausible solutions, thus challenging the concept of an average structure for this material.

Explanation of the stacking disorder in the β-phase of Pigment Red 170

Possible stacking sequences of this organic layer structure were derived by order–disorder theory. Lattice-energy minimizations revealed local structures and stacking probabilities, and explained the disorder and the diffuse scattering observed by X-ray single-crystal, powder and electron diffraction.

High-temperature structural study of decagonal Al–Cu–Rh

This article discusses the structural variation of decagonal Al–Cu–Rh as a function of temperature.

The quasiperiodic average structure of highly disordered decagonal Zn–Mg–Dy and its temperature dependence

The results of the first quantitative structure analysis of the Frank–Kasper decagonal Zn–Mg–Dy phase based on single-crystal X-ray diffraction data taken at different temperatures are reported.

Topological analysis of electron density and the electrostatic properties of isoniazid: an experimental and theoretical study

The charge-density analysis of isoniazid reveals the electron-density distribution and its electrostatic properties. The topological study on hydrogen bonding shows the strength of intermolecular interactions.

Structure determination of three polymorphs of xylazine from laboratory powder diffraction data

This article is focused on the structure determination of three anhydrous xylazine hydrochloride forms by powder X-ray diffraction without X-ray monochromatization. The physical properties of the determined structures were analysed.

Structure determination from powder data without prior indexing, using a similarity measure based on cross-correlation functions

A method was developed and implemented for fitting a crystal structure to a powder pattern, even if the lattice parameters deviate strongly. The method is even successful for powder diagrams of very low quality. Applications include an automatic fit starting from predicted structures or isostructural compounds.

Structure determination of KLaS₂, KPrS₂, KEuS₂, KGdS₂, KLuS₂, KYS₂, RbYS₂, NaLaS₂ and crystal-chemical analysis of the group 1 and thallium(I) rare-earth sulfide series

Crystal structures of KLaS₂, KPrS₂, KEuS₂, KGdS₂, KLuS₂, KYS₂ and RbYS₂, which belong to the α-NaFeO₂ structural family (), have been determined as well as NaLaS₂, which is derived from the disordered NaCl structural type (). The article is accompanied by a crystal-chemical analysis of group 1 and thallium(I) rare-earth sulfides as well as by a table that critically considers the published data of this class of compounds.

Strong positive and negative deviations from Vegard's rule: X-ray powder investigations of the three quasi-binary phase systems BiSX_1 − xY_x (X, Y = Cl, Br, I)

Some of the t(x) functions (t = a, b, c) in the systems BiSX_1 − xY_x (X, Y = Cl, Br, I) exhibit strong deviations from linearity.

Comparison of the structural motifs and packing arrangements of six novel derivatives and one polymorph of 2-(1-phenyl-1H-1,2,3-triazol-4-yl)pyridine

The series of structures reported in this work illustrate the inherent unpredictability in the crystalline products of even closely related molecules. The main similarities in packing arrangements in the structures can be attributed to the formation of common intermolecular interactions.

X-ray resonant single-crystal diffraction technique, a powerful tool to investigate the kesterite structure of the photovoltaic Cu₂ZnSnS₄ compound

Cu/Zn disorder in Cu₂ZnSnS₄ has been investigated by the X-ray resonant single-crystal diffraction technique.

Complete crystal structure of deca­fluoro­cyclohex-1-ene at 4.2 K from original neutron diffraction data

The recently proposed crystal structure model of decafluorocyclohex-1-ene at 4.2 K is completed by an additional alternative molecular orientation. The structure is refined by the derivative difference method in the rigid-body approximation leading to perfect agreement between observed and calculated neutron powder patterns.