An investigation of a series of layered Zn-1,4-di­azabi­cyclo[2.2.2]octane metal–organic frameworks: local structure and adsorption properties of mixed-metal centre

Local structures and adsorption properties for mixed-metal pillar-layered Zn–1,4-di­aza­bicyclo­[2.2.2]octane metal–organic frameworks are reported.

Study on the structural phase transitions in NaSICON-type compounds using Ag₃Sc₂(PO₄)₃ as a model system

The superionic conducting Na Super-Ionic CONducting-type (NaSICON-type) material Ag₃Sc₂(PO₄)₃ was studied by single-crystal X-ray diffraction between 100 and 520 K. Two phase transitions were found, at 177 and 291 K. Full structural characterization of the three polymorphs is given for the first time.

Crystal structures and dielectric properties of 4,4′-di­methyl-6,6′-di­chloro­thioindigo (Pigment Red 181)

The crystal structures of low-temperature and high-temperature polymorphs of 4,4′-di­methyl-6,6′-di­chloro­thio­indigo were determined. The optical band gap of low-temperature polymorph is E_bg = 2.08 eV and the dielectric permittivity of the sample is 10.

Effect of disordered imidazole substructure on proton dynamics in imidazolium malonic acid salt

Proton conductivity in imidazolium malonate containing ordered (Im-I) and disordered (Im-II) cations exhibits a low activation energy of 0.50 eV, which decreases to 0.17 eV at 318 K. The effect of disordered (Im-II) cations on proton conductivity of Im-MAL is considered as a contribution of correlated dipolar switching of disordered hydrogen bonds (linking nitrogen atoms of Im-II with acid oxygen atoms) to the phonon-assisted proton diffusion in the ordered part of the crystal.

HAR, TAAM and BODD refinements of model crystal structures using Cu Kα and Mo Kα X-ray diffraction data

The application of quantum crystallography methods for refinement against Cu Kα X-ray diffraction data results in reliable final structures affected by systematic errors which are a result of insufficient information concerning ADPs in low-resolution data.

Polymorphism and surface diversity arising from stress-induced transformations – the case of multicomponent forms of carbamazepine

Labile multicomponent crystal forms of carbamazepine have been studied with an aim of identifying the structural and surface features that drive the outcome of thermal stress-induced transformations.

Disordered sodium alkoxides from powder data: crystal structures of sodium ethoxide, propoxide, butoxide and pentoxide, and some of their solvates

The crystal structures of NaOEt, NaOPr, NaOBu and NaOAm (Am = amyl = pentyl) were determined from powder data. These compounds crystallize in an anti-PbO structure in the space groups P2₁m and P4/nmm. Additionally, solvates with the composition NaOEt·2EtOH, NaOPr·2PrOH, NaOⁱPr·5ⁱPrOH and NaO^tAm·^tAmOH were synthesized, and their structures were determined from single crystals. They form interesting chain structures of different compositions and topologies.

The role of hydrogen bonding in the incommensurate modulation of myo-inositol camphor ketal

The incommensurate modulation of myo-inositol-2,3-D-camphor ketal is due to a complex diperiodic hydrogen-bonding network.

Size-dependent strain in fivefold twins of gold

The strain distributions in sub-10 nm fivefold twins of gold have been analyzed com­bining aberration-corrected transmission electron microscopy and first-principles calculations. Bending of atomic planes has been measured in both experiments and calculations, and its contribution to the filling of the angular gap was shown to be size dependent.

Concomitance of octamolybdate isomers in metastable crystal structures isolated using homoleptic Co^II/Co^III complexes as structure-directing templates

The solid-state concomitance of octamolybdate isomers α–β, γ–β or β_cs–β_gp is driven by using [Co(bpy)₃]ⁿ⁺ (bpy = 2,2′-bi­pyridine; n = 2 or 3) cations, which adapt their cation–cation interactions and electronic properties to perform a templating role.

One-dimensional composite host–guest structure in BaVS₃

In an electronically complex quasi-one-dimensional BaVS₃ metal, a composite host–guest structure consisting of a BaS₃ hcp matrix as the host and V-chains as the guest are identified. The composite structure was identified at 295 K and at around 130 K the two structural subsystems lock together. As a result, the crystal symmetry changes, implying a structural phase transition, which was overlooked before.

Single-crystal neutron and X-ray diffraction study of garnet-type solid-state electrolyte Li₆La₃ZrTaO₁₂: an in situ temperature-dependence investigation (2.5 ≤ T ≤ 873 K)

Single-crystal neutron and X-ray diffraction methods were used to evaluate the exact crystal structure, Li site occupation and diffusion path of nominal Li₆La₃ZrTaO₁₂ at six temperatures between 2.5 K and 873 K.

Synthesis, crystal structure and structure–property relations of strontium orthocarbonate, Sr₂CO₄

A new orthocarbonate, Sr₂CO₄, was synthesized under extreme pressure and temperature conditions of 92 GPa and 2500 K, respectively. The crystal structure of the compound s fully characterized in situ by synchrotron single-crystal X-ray diffraction and DFT calculations were employed to provide insight into its equation of state, Raman and IR spectra, and bonding.

Structure of 1,6-anhydro-β-D-gluco­pyranose in plastic crystal, orientational glass, liquid and ordinary glass forms: molecular modeling and X-ray diffraction studies

Modeling the structure of levoglucosan in plastic crystal, orientational glass, liquid and ordinary glass forms is reported here.

The crystal structure and thermal decomposition kinetics of cis-hexa­nitro­stilbene

The crystal structure of cis-hexanitrostilbene (cis-HNS) was determined by Fourier transform infrared spectroscopy, NMR spectroscopy and single-crystal X-ray diffraction. The thermal decomposition kinetics of cis-HNS were studied by differential scanning calorimetry, and it was found that when the heating rate is low, cis-HNS undergoes a crystal transformation, from liquid cis-HNS to liquid trans-HNS, and then it will solidify and release heat.

The crystal structure of Cu₂GeSe₃ and the structure-types of the I₂-IV-VI₃ family of semiconducting compounds

Contrary to what has previously been reported, the structure of Cu₂GeSe₃ is found to be monoclinic (Cc, No. 9) and not orthorhombic (Imm2, No. 44) due to distortions as expected from bond valence model considerations.

A half-salamo-based pyridine-containing ligand and its novel Ni^II com­plexes including different auxiliary ligands: syntheses, structures, fluorescence properties, DFT calculations and Hirshfeld surface analysis

Three novel multinuclear Ni^II com­plexes with a half-salamo-based pyridine-containing ligand have been synthesized and characterized by FT–IR, UV–Vis absorption spectroscopy, X-ray crystallography, Hirshfeld surface analysis and density functional theory (DFT) calculations.

Cementitious Materials Science. Theories and Applications. Edited by Lin Zongshou, Xing Weihong and Chen Wei. De Gruyter, 2019. XIII + pp. 403, Paperback. Price EUR 68.95. ISBN 978-3-11-057209-4

Polymorphism in Molecular Crystals. Second Edition