Introducing the Best practice in crystallography series

The first three articles of the new `Best practice in crystallography' series have been published covering a guide to growing crystals for single-crystal diffraction studies, a guide to performing photocrystallography and a review detailing what aspects of crystal structure are of particular importance to determining electrical conductance in organic materials.

Methods in mol­ecular photocrystallography

Over the last three decades, the technology that makes it possible to follow chemical processes in the solid state in real time has grown enormously. These studies have important implications for the design of new functional materials for applications in optoelectronics and sensors. Light–matter inter­actions are of particular importance, and photocrystallography has proved to be an important tool for studying these inter­actions.

On the importance of crystal structures for organic thin film transistors

Knowledge of the mol­ecular packing within the crystal structures of organic semi­con­duc­tors has been instrumental in understanding their solid-state electronic properties. Crystal structures are thus becoming increasingly important for enabling engineering properties, understanding poly­mor­phism in bulk and in thin films, exploring dynamics and elucidating phase-transition mech­a­nisms.

3D electron diffraction studies of synthetic rhabdophane (DyPO₄·nH₂O)

3D ED studies of synthetic rhabdophane allow single-crystal structure solution from individual nanocrystals and provides insight into the disordered water arrangment in the material. This highlights the usefulness of this technique to study order/disorder at nanoscale and its potential in exploring the effects of irradiation-induced structural and phase changes at such scales in the near future.

Experimental and theoretical structural investigation of an ionic Nd coordination polymer

We have successfully synthesized a novel ionic neodymium coordination polymer with 4-sulfobenzoate and pyridine-4-carbohydrazide ligands. The network is characterized by an anionic one-dimensional chain within a cationic three-dimensional polymer, which has potential voids if the one-dimensional net is changed for a smaller anionic species. The structural characterization was achieved by single-crystal X-ray diffraction and com­putational calculations.

Synthesis, crystal structure, magnetic behaviour and thermal stability of a paddle-wheel copper(II) com­plex bearing equatorial 3,4-di­ethoxybenzoate ligands

A binuclear paddle-wheel copper(II) com­plex containing substituted benzoates as equatorial bridging ligands and ethanol as axial ligands exhibits an anti­ferromagnetic exchange coupling of 2J = −288 cm⁻¹, which fits well into a previously suggested magneto-structural correlation.

2D coordination polymers of cadmium(II) and zinc(II) derived from N,N′-bis­(glycin­yl)pyromellitic di­imide: microwave-assisted synthesis, structures, spectroscopic properties and influence of metal-ion size

Two 2D coordination polymers (CPs) were synthesized by the microwave-irradiated reaction of N,N′-bis­(glycin­yl)pyromellitic di­imide (BGPD) with cadmium acetate dihydrate and zinc acetate dihydrate, respectively. The com­plexes show different structures and photoluminescence properties. Inter­molecular π–π, hy­dro­gen-bonding and carbon­yl–carbonyl (n→π*), as well as lone-pair⋯π, inter­actions are operative in the crystal packing. The influence of the metal-ion size on the structures of the CPs based on the BGPD ligand has been explored through a com­parative analysis of the diverse structures with different metal ions.

A new three-dimensional barium(II) coordination polymer con­structed from N,N′-bis­(glycin­yl)pyromellitic di­imide: microwave-assisted synthesis, structure, Hirshfeld surface analysis and properties

A new three-dimensional coordination polymer, with a 5-connected hexa­gonal boron nitride net (bnn) topology, was synthesized by the microwave-irradiated reaction of N,N′-bis­(glycin­yl)pyromellitic di­imide (BGPD) with barium nitrate. The thermal stability and photoluminescence properties, as well as the UV–Vis absorption spectra, of the coordination polymer were investigated.

The influence of the axial group on the crystal structures of boron sub­phthalo­cyan­ines

The crystal structures of an array of 16 boron sub­phthalo­cy­an­ines with structurally diverse axial groups were analyzed and com­pared based on their inter­molecular inter­actions, axial bond lengths and bowl depths.

Revisiting a natural wine salt: calcium (2R,3R)-tar­trate tetra­hydrate

In the salt calcium (2R,3R)-tar­trate tetra­hydrate, the absolute configuration was established unambiguously using anomalous dispersion effects in the diffraction patterns. High-quality data also allowed the location and free refinement of all the H atoms.

Crystal structures and properties of derivatives of the alkaloid matrine: salts and hydrate forms

The crystal structures of two salts and one hydrate form of the tetra­cyclo­quinolizidine alkaloid matrine are described. Hirshfeld and thermal analysis have also been carried out.