Themed collection A celebration of 25 volumes of CrystEngComm

High pressure offers insight into the mechanisms of a wide range of solid-state phenomena occurring under atmospheric pressure conditions.

Metal oxide nanoparticles are an important class of nanomaterials that have found several applications in science and technology.

Alleviating the energy & safety contradiction of energetic materials through crystal engineering.

Cocrystallization technology offers a promising platform for energetic materials to achieve a desired balance between high detonation performance and low sensitivity. This paper highlights the up-to-date progress of energetic cocrystals.

During the various applications of MOFs, the photoluminescence properties of MOFs have received growing attention, especially for nitroaromatics (NACs) sensing. In this highlight, we summarize the progress in recent research in NACs sensing based on MOFs and sensing applications for nano-MOF type materials and MOF film.

In the past few decades, much effort was put into the development of synthetic strategies to produce nanoparticles of different sizes and morphologies and a large number of scientific contributions are dedicated to the characterization and application of metal nanoparticles.

A review of the inclusion of organic matter within single crystalline hosts: from biogenic minerals to bio-inspired nanohybrid single crystal composites.

Recent developments of transition-metal oxide nanostructures with designed shape and dimensionality, including various synthesis methods and applications, are presented.

A working hypothesis for the understanding of amorphous-to-crystalline transformations in biogenic skeletal materials formed through transient amorphous precursor phases.

We review the current state of the art in molecular simulations and modelling of MOFs for hydrogen storage.

The fabrication of metal nanoparticles in porous host matrices, especially metal–organic frameworks, has become of great interest in the last years and will be comprehensively discussed in this article.

TTF and its derivatives were applied in organic field-effect transistors (OFETs).

Cocrystals have gained much interest in recent years owing to their potential to improve the physicochemical properties of the parent compounds. We present a survey of polymorphic cocrystals focussing on different types of polymorphs and emphasize the impact of polymorphism on the performance of cocrystals with representative examples.

Cheap energy calculations and readily prepared dynamic pictures outline a Boylean–Copernican view of crystal structure and intermolecular interactions.

Role of mechanochemistry in the synthesis of new pharmaceutical materials.

The current highlight summarizes the importance of interactions involving organic fluorine and their role in crystal engineering, polymorphism and ab initio studies.

Strategies for fabrication and stabilization of porous molecular networks: via template-assisted self-assembly or concentration in control.

Recent advances in organic–inorganic perovskites are reviewed with particular emphasis on developments in novel <110>-oriented structures, film preparation, patterning methods, templating engineering and optoelectronic properties of hybrid perovskites.

The recent progress on establishing the structure–mechanical property correlation in molecular crystals studied by qualitative mechanical (shearing, bending and brittle) tests, nanoindentation, powder compaction and high-pressure study methods is discussed in the context of crystal engineering. Using an interdisciplinary approach, the anisotropic mechanical behaviour in molecular crystals may be studied in a systematic way for a deeper understanding of the fundamentals.

Recent advances and new trends in crystal engineering are highlighted with particular emphasis on developments in intermolecular interactions, notably hydrogen and halogen bonds; metal–organic frameworks; polymorphism and solvates.

Hirshfeld surface analysis ventures beyond the current paradigm to view molecules as “organic wholes”, thereby fundamentally altering the discussion of intermolecular interactions through an unbiased identification of all close contacts, coupled with novel visualization tools.

Crystal polymorphism is efficiently probed by lattice phonon micro-Raman spectroscopy. Raman mapping is a powerful method to control phase homogeneity and phase mixing in organic semiconductors with applications in molecular electronics.

The nature and characteristics of the CH/π interaction are discussed by comparison with other weak molecular forces such as the CH/O and OH/π interaction. The consequences of CH/π hydrogen bonds in supramolecular chemistry are reviewed on grounds of recent crystallographic findings and database analyses.

Two isostructural 3D dynamic MOFs with different metal sites have been constructed, which exhibit temperature-dependent stepwise and hysteretic sorption behaviors toward CO₂ around room temperature.

The pK_a rule is validated and quantitated on a dataset of 6465 acid–base (AB) crystalline complexes using pK_a prediction models.

The crystal size and morphology of ZIF-8 crystals can be fine-tuned using surfactant CTAB as a capping agent in aqueous systems.

CoAl LDH and its derivatives with a flower-like morphology were successfully synthesized via some phase transition routes.

Both the MOFs proved to be good candidates for the photocatalytic degradation of methyl violet. The mechanism of these photocatalytic degradations is discussed.

Selective adsorption of surfactants was theoretically predicted on crystal faces to prepare well-dispersed nanoparticles for the self-assembly of a high-quality stable dielectric constant film.

Lattice energy, entropy and free energy differences for over 500 pairs of known polymorphs are computed and discussed.

Bulk crystal of tetragonal CH₃NH₃PbI₃ with dimensions of centimeters grown by a temperature-lowering method in HI solution is reported for the first time.

The catalytic activity of the Zr-benzenedicarboxylate (Zr-BDC) UiO-66 increases by using synthesis modulators as trifluoroacetate (TFA) or hydrochloric acid (HCl), which can be removed post-synthetically.

Poorly hydrated/anhydrous ACC with a protocalcite structure forms after spinodal decomposition and hydrated ACC precipitation and transforms into calcite in air/room temperature via interface-coupled dissolution/precipitation.

A facile synthesis of graphene–ZnO nanorod nanocomposites for liquid-phase photocatalytic degradation of dye under ultraviolet light irradiation has been performed, which suggests the promising potential of fabrication of 1D ZnO nanorod semiconductor–2D graphene nanocomposites for various photocatalytic applications.

We report here the synthesis of a zeolitic imidazolate framework-8 (ZIF-8) in an aqueous solution.

Nanostructured MnO₂ supercapacitors with various morphologies can be crystallized via the redox reaction of KMnO₄ and NaNO₂.

Co-crystallisation of CL-20 with a selection of co-former molecules provides important information about the dominant intermolecular interactions and the relative favourability of different molecular conformations of CL-20.

Three kinds of 3D-hierarchical SnS₂ micro/nano-structures were synthesized by controlling the use of L-cys and their Li storage properties were studied.

Isosurfaces of the procrystal electron density can be used to locate, visualise and quantify void space in molecular crystals. The method is capable of locating and characterising all “empty” space in molecular crystals. Results for crystalline systems including porous dipeptides, metal–organic and covalent organic frameworks illustrate the potential of this new approach.

Liquid-assisted grinding (LAG) and sonochemical (SonicSlurry) techniques in cocrystallisation were compared by introducing a parameter (η) that allows interpreting and predicting cocrystal formation in a range of solvents and concentrations by considering reactant saturation levels.

Four different screening techniques were used to identify cocrystals of carbamazepine containing pharmaceutically acceptable carboxylic acids. Strategies for generating supersaturation of the cocrystal and avoiding crystallizing the individual reactants are discussed.

The B3LYP method augmented with a damped empirical dispersion term (B3LYP-D*) is shown to yield structures and cohesive energies, for a representative set of molecular crystals, in excellent agreement with experimental data

Molecular electrostatic potentials mapped onto Hirshfeld surfaces and displayed within a crystal packing diagram can be used to rationalize close molecular contacts in crystals.

A new method of “structural genetic fingerprinting” that allows a quantified comparison of whole molecular crystal structures is described.

Binary and ternary cocrystals of carboxylic acids with bipyridine bases have linear and zigzag tapes and flat and corrugated sheet structures mediated by neutral and ionic acid⋯pyridine synthons. A modified ΔpK_a rule to predict the nature of H bond in COOH–pyridine cocrystals is proposed.

The likelihood is considered of organic molecules to crystallise as hydrates depending of the polarity of the functional groups in their molecules, and the way of embedding water clusters in a larger H-bond network forming an extended pattern is discussed.