Demystifying density functional theory for the crystal engineering community

The tutorial on best practices in `0 K' DFT energy calculations on mol­ecular crystal structures by van de Streek & Johnson [Acta Cryst. (2026), C82, 383–400] provides a highly accessible and practical guide for performing reliable periodic density functional theory calculations in organic crystals.

Synthesis, structural characterization, and electronic structure of monoclinic α-[SeCl₃][MoOCl₄]

Moisture-sensitive tri­chlorido­selenium tetra­chlorido­oxidomolybdate, α-[SeCl₃][MoOCl₄], was synthesized from MoOCl₄ and Se₂Cl₂, and structurally characterized by single-crystal X-ray diffraction, revealing a layered ionic solid com­prising [SeCl₃]⁺ cations and dimeric [Mo₂O₂Cl₈]²⁻ anions linked through secondary Se⋯Cl inter­actions, with electronic structure analysis indicating semiconducting behavior.

When the crucible contributes: serendipitous formation, flux reactivity, and crystal and electronic structures of two aluminium-bearing mixed-metal oxides, Ba_2.1Pb_0.9Al_8.8In_2.2O₂₀ and BaAl_1.6Ga_0.4O₄

Alumina crucibles act as unintended aluminium sources in Pb-flux syntheses, yielding two heavily disordered metal oxides, with Pb₃GeAl₁₀O₂₀- and BaZnGeO₄-related structures.

EuSnAs: the first arsenide adopting the NbCrN structure type

EuSnAs was discovered as the first arsenide adopting the tetra­gonal NbCrN structure type and its layered structure features corrugated Sn sheets separated by [EuAs] slabs.

Crystal structures and supra­molecular and Hirshfeld surface analysis of three novel 2,4,6-tri­amino­pyrimidine salts

Three hydrous tri­amino­pyrimidine (TAP) salts were synthesized and structurally characterized. All three exhibit protonation at the N1 position and form R₂²(8) TAP–carboxyl­ate heterosynthons. Structural diversity arises from anion topology and hydration, yielding tetra­mers, chains and 3D frameworks. Hirshfeld analysis highlights dominant H⋯H contacts, with O⋯H and N⋯H inter­actions directing supra­molecular assembly and dimensionality.

Structures of hexa­kis­(anti­pyrine)lead(II) com­plexes: the first example of the stereochemically active and inactive 6s² lone pair for one lead(II) com­plex

Single-crystal X-ray diffraction studies on [Pb(anti)₆]X₂ (anti = antipyrine; X = OTf⁻ and ClO₄⁻) com­pounds revealed for the triflate salt, the formation of two polymorphs with both holodirected regular octa­hedral geometry (eccentricity value ɛ = 0) and hemidirected symmetry of a ψ-penta­gonal bipyramid (ɛ = 0.14). This work demonstrates, for the first time, that one lead(II) ion can exhibit both active or inactive 6s² lone-pair character in a com­plex.

Synthesis, crystal structure and green lu­mines­cence of a novel manganese(II)-based hybrid: bis­[(tert-but­oxy­carbon­yl)methyl­tri­phenyl­phospho­nium] tetra­chlorido­manganate(II)

A novel phospho­nium-based manganese(II) hybrid crystal, (TBTP)₂[MnCl₄] [TBTP is (tert-but­oxy­carbon­yl)methyl­tri­phenyl­phospho­nium], displays green lu­mi­nes­cence with a millisecond-scale lifetime (515 nm, 2.83 ms), attributed to the Mn^{2+ 4}T₁→⁶A₁ transition. Electronic structure analysis reveals a spatial separation of frontier orbitals, a structural feature that may aid in achieving the long-lived emission.

Single-crystal structure determination of psilocybin after dehydration

The structures of the hydrous and first anhydrous phases of crystalline psilocybin have been determined using single-crystal X-ray diffraction.

YK-4-250, a synthetic telmisartan–tempol conjugate: crystal structure of a stabilized free radical containing an angiotensin AT₁ receptor inhibitor

The first crystal structure of the telmisartan–tempol conjugate YK-4-250 is reported, revealing the intra­molecular C–H⋯π inter­actions that stabilize the nitroxide radical while preserving the angiotensin AT₁ receptor antagonist pharmacophore.

Tuning helical chirality and physical properties in chiral lactate-based coordination polymers by varying metal centres and auxiliary ligands

By altering the metal centre and auxiliary ligand, two chiral lactate-based coordination polymers exhibit distinct helical chirality expressions and properties.

Multicom­ponent crystals of nitro­imidazole drugs with tri­thio­cyanuric acid: two com­peting drug–coformer supra­molecular motifs

Tri­thio­cyanuric acid forms either R₂²(8) dimers or linear chain motifs in nitro­imidazole cocrystals, giving rise to two com­peting drug–coformer supra­molecular binding schemes.

Peculiarity of atomic dis­place­ments in garnets discovered through a single-crystal X-ray diffraction study of the Na-bearing vanadate garnet series

Garnets where the mean-square dis­place­ments of the tetra­hedral cations are largest in the direction of adjacent dodeca­hedral cations were discovered through structure refinements of the Na-bearing vanadate garnet series. This peculiar atomic dis­place­ment behaviour occurs when the dodeca­hedral sites are occupied by different cation species with different valences and largely different sizes.

Water-bridged tetra­meric supra­molecular synthons in a novel tetra­substituted imidazole–phenyl­alanine derivative synthesized via a Debus–Radziszewski reaction

A new imidazole derivative of phenyl­alanine was synthesized, the crystals displaying dimeric and/or tetra­meric structures with unusual water double bridges.