Introduction to the magnetic structures special issue

The virtual special issue on Magnetic Structures is introduced. The articles included here were originally published in recent regular issues of Acta Crystallographica Section B.

Subtle details revealed via powder diffraction and validated by charge flipping

Lake and Von Dreele [Acta Cryst. (2025), B81, 572–581] provide an informative look at the current state of the art in powder diffraction, and subtleties that can be revealed through its careful application.

The glycolipid flocculosin-A from the fungus Anthracocystis flocculosa, or how to deal with cotton-wool-like crystals

Crystals of flocculosin-A, the major antifungus compound from Anthracocystis flocculosa, are optimised using a cyclic temperature control.

The charge density and force-field view of bonding interactions in crystals with photomechanical properties: [Co(NH₃)₅NO₂]ClNO₃ versus [Co(NH₃)₅ONO]ClNO₃

The quantum crystallography approach used here reveals the fine features of the interatomic interactions of different nature in [Co(NH₃)₅NO₂]ClNO₃ and [Co(NH₃)₅ONO]ClNO₃ crystals and provides a better insight into the role of the crystalline environment in the intramolecular nitro–nitrito linkage photoisomerization.

DMSO solvates of tert-butyl­calix[6]arene and related multisolvent structures

This study highlights how solvent properties, host–guest interaction energies and packing preferences govern the solid-state organization of tert-butyl­calix[6]arene, a macrocycle of importance in separation, molecular recognition and supramolecular chemistry.

Magnetoelastic effect in R₅Pt₂In₄ (R = Tb–Tm) investigated by neutron powder diffraction

Magnetoelastic effect in R₅Pt₂In₄ (R = Tb–Tm) is determined from neutron powder diffraction data.

Unveiling the structure and interactions of silicene grown on MoS₂: insights from hybrid molecular dynamics simulations

The stable epitaxial growth of silicene on MoS₂ requires both van der Waals and covalent interactions – without them, the silicene collapses into a disordered state. These findings offer important insights into designing stable silicene/MoS₂ heterostructures for future nanotechnology applications.

Structural and computational studies of new Schiff base ligands derived from 2-(methyl­amino)- and 2-(ethyl­amino)­benzaldehyde: synthesis, characterization, QTAIM, NCI plot, TD-DFT and energy decomposition analysis

Three new Schiff base ligands are characterized. The presence of intra- and intermolecular interactions in the compounds are established by QTAIM theory and noncovalent interaction plot computational method. Hirshfeld surface analysis reveals that the most abundant intermolecular contacts are H⋯H contacts. The interaction energies of the dimer associates of the compounds through the intermolecular interactions in their solid-state are obtained by energy decomposition analysis via natural orbitals for chemical valence theory.

OD (order–disorder) interpretation and diffuse scattering analysis of an organic polytype with allotwin character: a detailed how-to

The complex stacking disorder of 2,3-dihydroxy-1,3,4-trimethyl-6-oxo-1,4-cyclohexadiene-1-carboxylic is analyzed by applying the order–disorder theory and its diffuse scattering is interpreted using a growth model.

Crystal structure analysis of van der Waals layered phospho­rus chalcogenide CuVP₂S₆

Two-dimensional van der Waals layered compound CuVP₂S₆ is studied by transmission electron microscopy and single-crystal X-ray diffraction. Rotational microtwin structures, which may be typical and characteristic of two-dimensional van der Waals compounds, are observed.

The structures of mcgovernite and carlfrancisite reconsidered: static disorder or ordered defects and twinning?

A reconsideration of the crystal structures of mcgovernite and carlfrancisite gives noncentrosymmetric structures with ordered planar defects instead of random site disorder in centrosymmetric ones.

A case for resonant X-ray Bragg diffraction by a collinear antiferromagnet Li₂Ni₃P₄O₁₄

Amplitudes for resonant X-ray diffraction by collinear antiferromagnet Li₂Ni₃P₄O₁₄ that include permitted Dirac multipoles, e.g. anapoles, are investigated. Chiral signatures for the rotation of X-ray helicity are described.

Prediction and analysis of symmetry-raising transitions in anilinium tetra­fluoro­borate

Three symmetry-raising phase transitions of anilinium tetrafluoroborate between room temperature and 490 K have been structurally characterized using powder and single-crystal diffraction, dielectric measurements, NMR and group–subgroup relationships.

Probing the local structure of Bi₂O₃ chemical derivatives: the neglected cation sublattice

The importance of the cation sublattice in influencing both the average and local structures of δ-Bi₂O₃-like phases is highlighted. It also reveals the inadequacy of conventional average structural analysis methods in describing comprehensively the structure of real materials.