The challenges of growing great crystals – or at least good enough ones!

The article of Sommer [Acta Cryst. (2024), C80, 337–342] provides a concise and effective introduction to the subject of growing crystals suitable for structure determination.

Di­carbonyl[10,10-di­methyl-5,15-bis­(penta­fluorophenyl)biladiene]ruthenium(II): discovery of the first ruthenium tetra­pyrrole cis-di­carbonyl complex by X-ray and electron diffraction

The structure of a CO₂ reduction photo­catalyst prototype, the first cis-dicarbonyl ruthenium(II) tetra­pyrrole complex, has been determined by X-ray and electron diffraction to have an unprecedented seesaw-coordinated biladiene ligand.

A brief review on com­puter simulations of chal­copy­rite surfaces: structure and reactivity

Review of com­putational simulations of the chal­co­py­rite structure, oxidations and inter­actions with collectors.

2,4-Di­aryl­pyrroles: synthesis, characterization and crystallographic insights

The crystallographic analysis of two novel pyrroles is reported. A nitrosyl derivative revealed strong hydrogen-bond inter­actions and bifurcated halogen bonds that lead to inter­stitial voids.

Further evaluation of the shape of atomic Hirshfeld surfaces: M⋯H contacts and homoatomic bonds

The sensitivity of atomic Hirshfeld surfaces is further validated through the evaluation of contacts of type M⋯H and through the variations in curvature for C—C bonds depending on the hybridization of the C atoms.

Multivalent hy­dro­gen-bonded architectures directed by self-com­plementarity between [Cu(2,2′-bi­imid­azole)] and malonate building blocks

This study unveils the intricate crystal structures and diverse supra­molecular architectures of four novel Cu^II com­plexes with 2,2′-bi­imid­az­ole and malonate ligands, showcasing their unique hy­dro­gen-bonded networks and their potential for use in materials science applications.

Crystal structures of two unexpected products of vicinal di­amines left to crystallize in acetone

Two ben­zo­di­az­e­pines, obtained in attempts to crystallize vicinal amines from acetone, are examined. The findings are relevant to understanding the role of solvents during crystallization processes.

Coordination structure and inter­molecular inter­actions in copper(II) acetate com­plexes with 1,10-phenanthroline and 2,2′-bi­pyri­dine

This study uses geometric parameters and Hirshfeld surfaces to understand and com­pare the coordination and the geometric distortion of a series of copper com­plexes exhibiting one acetate and two nitro­genous ligands (bipy or phen). It also focuses on understanding how the O atoms of the acetate ligand inter­act with the metal centre and the role this ligand can play in the geometry distortion.

Salt forms of amides: protonation of acetanilide

Treating acetanilide with aqueous strong acids gives protonation at the amide O atom and a series of anhydrous hemi-protonated salt forms of this simple amide.

Occupational modulation in the (3+1)-dimensional incommensurate structure of (2S,3S)-2-amino-3-hy­droxy-3-methyl-4-phen­oxy­butanoic acid dihydrate

The (3+1)-dimensional incommensurate structure of (2S,3S)-2-amino-3-hy­droxy-3-methyl-4-phen­oxy­butanoic acid dihydrate (I·2H₂O), in which one of the water mol­ecules is disordered over two positions and each position exhibits occupational modulation, can be well refined in superspace, and in the average and supercell approximations. The occupational modulation of the disordered solvent water mol­ecule results from the com­petition between the different hy­dro­gen-bonding motifs associated with the two disorder positions of the water mol­ecule.

Formation of a di­iron–(μ-η¹:η¹-CN) com­plex from aceto­nitrile solution

A di­iron end-on μ₂-η¹:η¹-CN-bridged com­plex is obtained from a crystallization experiment of an open-chain iron–NHC com­plex. The cyanide appears to originate from the aceto­nitrile (MeCN) solvent by C—C bond cleavage or through carbon–hy­dro­gen oxidation.

A luminescent Cu₂I₂P₂S₂-type binuclear com­plex and its fluorescence sensing for pyridine

In the title Cu₂I₂P₂S₂-type binuclear com­plex, Cu₂I₂TPP₂TU₂, TPP (triphenylphosphine) and TU (thiourea) adopt terminal coordinations, and the two Cu^I centres are bridged by two μ₂-I ligands. After com­posite processing, the paper-based film based on the title com­plex exhibits obvious luminescence light-up sensing for pyridine and 4-methyl­pyridine.

Crystal structures, phase transition, and Hirshfeld surface analyses of the bromide and chloride congeners of aqua­[2,4,6-tris­(pyri­din-4-yl)-1,3,5-tri­azine]zinc(II) halide

The crystallization conditions leading to the production of the title metal–organic com­plexes aqua­[2,4,6-tris­(pyri­din-4-yl)-1,3,5-tri­a­zine]zinc(II) bromide and chloride, along with the structural characterization, temperature-induced phase transition of the bromide congener, supra­molecular analysis using Hirshfeld surfaces, and two-dimensional fingerprint plots, are reported. In both structures, inter­molecular hydrogen bonding involving the zinc-bound water and pyridyl N atoms is a key inter­action that underpins the three-dimensional supra­molecular network.

Role of secondary inter­actions in a series of 2:1 halogen-bonded cocrystals formed between 4-(di­methyl­amino)­pyridine and ditopic halogen-bond donors

The role of secondary noncovalent inter­actions in the structures of a series of 2:1 cocrystals of ditopic halogen-bond donors and 4-(di­methyl­amino)­pyridine is analyzed.

Concerning the structures of Lewis base adducts of titanium(IV) hexa­fluoro­iso­pro­pox­ide

The reaction of titanium(IV) chloride with sodium hexa­fluoro­iso­pro­pox­ide, carried out in hexa­fluoro­iso­propanol, produces titanium(IV) hexa­fluoro­iso­pro­pox­ide, which is a liquid at room temperature. Recrystallization from coordinating solvents, such as aceto­nitrile or tetra­hydro­furan, results in the formation of bis-solvate com­plexes. These com­pounds are of inter­est as possible Ziegler–Natta polymerization catalysts.

Two polymorph modifications of tris­(hexa­fluoro­acetyl­aceton­ato)iron(III) revealed: is that common for other trivalent metals?

The X-ray structural characterization of the iron(III) hexa­fluoro­acetyl­acetonate high-tem­per­a­ture polymorph reveals its structure as trigonal, which is different from the previously reported monoclinic low-tem­per­a­ture polymorph. The transformation between the two polymorphs was studied upon crystallization from the gas phase, melt, and from solution at different tem­per­a­tures.

Coordination variety of phenyl­tetra­zolato and di­methyl­amido ligands in dimeric Ti, Zr, and Ta com­plexes

The first example of a nonbridging η²-coordination of a tetra­zolato ligand to a d-block element (Zr) is reported. Three related dinuclear 5-phenyl­tetra­zolato com­plexes of Ti, Zr, and Ta are structurally characterized.