A new home for studies of crystal growth and characterisation

Acta Crystallographica Section B launches a new section on crystal growth and actively welcomes submissions which match the scope of the journal.

Detailed analysis of deformation potentials with application in orbital-free density functional theory

This work presents a detailed analysis of the recently published deformation potentials for application in orbital-free density functional theory, that are able to take the interaction between atoms into account through the help of their electron densities only. It is shown that the present ansatz provides a systematic pathway beyond the recently introduced atomic fragment approach.

Developing orbital-free quantum crystallography: the local potentials and associated partial charge densities

The electrostatic, exchange, Weizsacker and Pauli potentials, as well as associated partial electron densities, reconstructed from experimental electron density using the orbital-free density functional theory formalism, are applied for the bonding analysis for a heteromolecular crystal of ammonium hydro­oxalate oxalic acid dihydrate.

Bonding features in Appel's salt from the orbital-free quantum crystallographic perspective

Experimental charge density is applied for covalent and noncovalent bond characterization in Appel's salt (4,5-di­chloro-l,2,3-di­thia­zolium chloride). The chalcogen and halogen bonds are categorized using the gradient fields of electron density and electrostatic potential.

Pressure-induced structural phase transitions in bis­muth tungstate Bi₂WO₆

The pressure-induced structural polymorphism in bismuth tungstate Bi₂WO₆ has been investigated by neutron diffraction and Raman spectroscopy.

Solid-state electronegativity of atoms: new approaches

A system of atomic electronegativities is suggested, specially devised to describe atoms in solids, rather than isolated molecules.

Crystal structure or chemical composition of salt–sugar-based metal–organic frameworks: what are the nonlinear optical properties due to?

Two new isomorphous metal–organic frameworks of formula [Ca(C₆H₁₂O₅)₂]X₂ have been synthesized and the parameters influencing their nonlinear optical response investigated.

Positron lifetime spectroscopy of defect structures in Cd_1–xZn_xTe mixed crystals grown by vertical Bridgman–Stockbarger method

Positron lifetime spectroscopy reveals the systematic evolution of open-volume defects as a function of Zn content in Cd_1–xZn_xTe mixed crystals grown by the Bridgman–Stockbarger method. The direct correlation between the structural defects, the lattice disorder (estimated by X-ray diffraction) and the lattice thermal conductivity is found. Shallow positron traps indicate the presence of impurities undetectable by other defect characterization techniques.

The influence of chalcogen atom on conformation and phase transition in chalcogenazinoquinolinium monoiodides

The results of combined use of experimental diffraction and spectroscopic techniques and theoretical approaches characterizing structure, properties and low-temperature phase transition of chalcogenazinoquinolinium monoiodides are reported here.

Recommended X-ray single-crystal structure refinement and Rietveld refinement procedure for tremolite

This study aims to solve the site-occupancy issues of any crystalline substance, showing that the structure refinement results should not be limited to a simple description of the crystal geometry but should go beyond that, providing refined site-scattering values consistent with the chemical data.

Czochralski growth of mixed cubic sesquioxide crystals in the ternary system Lu₂O₃–Sc₂O₃–Y₂O₃

The phase diagram of the ternary system Lu₂O₃–Sc₂O₃–Y₂O₃ is investigated and compositions with melting points below 2200°C are found. This allows for the first successful growth of the mixed cubic sesquioxide crystal (Er_0.07Sc_0.50Y_0.43)₂O₃ by the Czochralski method from an iridium crucible.

Room-temperature ferroelasticity and unusual sequence of phase transitions in the crystal of (N₂H₅)₃[CdCl₅]

Phase transitions for the (N₂H₅)₃[CdCl₅] crystal are unique due to the fact that the first heating run results in different structural changes compared to those observed during cooling and subsequent heating/cooling runs.

Crystal structure and hyperfine interactions of delafossite (CuFeO₂) synthesized hydro­thermally

X-ray diffraction and Mössbauer spectroscopic studies of hydro­thermally synthesized delafossite (CuFeO₂) were performed. Changes in the character of the hyperfine interactions in the magnetic transition temperature range are discussed.

A new topological semimetal candidate: SmMnBi₂

The crystal structure of SmMnBi₂, a new topological semimetal candidate, is investigated and compared to the structures of existing topological semimetals.

Low-temperature phase transition and magnetic properties of K₃YbSi₂O₇

A low-temperature displacive-type phase transition in K₃YbSi₂O₇ occurring at ≃ 210 K is reported, where the symmetry of the ambient-temperature polymorph decreases from hexagonal (space group P6₃/mmc) to orthorhombic (space group Cmcm). The structural relationships between the two polymorphs and their magnetic properties are described.

Comparison of the temperature- and pressure-dependent behavior of the crystal structure of CrAs

The dependences of the crystal structure of CrAs on temperature (30–400 K) and on pressure (0–9.46 GPa) are reported. The investigation shows twinning accompanying the temperature-induced isosymmetrical phase transition and the existence of a distinct Cr–Cr distance within the structure showing anomalous behavior.

Mg(H₂O)₂[TeO₂(OH)₄]: a polytypic structure with a two-mode disordered stacking arrangement

Crystals of the polytypic Mg(H₂O)₂[TeO₂(OH)₄] feature one-dimensional diffuse scattering owing to correlated disorder.

Crystal growth and physical properties of an antiferromagnetic molecule: trans-di­bromido­tetra­kis­(aceto­nitrile)chromium(III) tribromide, [CrBr₂(NCCH₃)₄](Br₃)

A novel 3d transition-metal com­plex, [CrBr₂(NCCH₃)₄](Br₃), was synthesized. A com­plete structural characterization, a detailed magnetic property study and theoretical evaluations were performed to illustrate the magnetic behavior of Cr³⁺ in a bromide and aceto­nitrile ligand coordination environment.

Properties and interactions – melting point of tri­bromo­benzene isomers

The melting points of tri­bromo­benzene isomers are correlated with the number, nature and distribution of intermolecular interactions in their structures.

2/1 and 1/1 cubic approximants in the ternary R-Cd-Mg (R = Y, Er) systems

The atomic structures of 2/1 and 1/1 quasicrystalline approximants in the ternary R-Cd-Mg (R = Y, Er) system are revealed using X-ray structural analysis.

First-principles investigation of V-doping effects on Fe₃Cr₄C₃ carbide in hypereutectic Fe–Cr–C hardfacing coating

The crystal structure of Fe₃Cr₃VC₃, obtained by V doping in Fe₃Cr₄C₃, exhibits better mechanical properties.

Crystal structure of copper perchlorophthalo­cyanine analysed by 3D electron diffraction

The structure of copper perchlorophthalo­cyanine (CuC₃₂N₈Cl₁₆, Pigment Green 7) was solved from three-dimensional electron diffraction data (3D ED) and placed into the series of known copper phthalo­cyanine crystal structures.