A library of ten complexes, [Yb(hfac)(L)] (1), [Yb(hfac)(OH)(L)] (2), [Dy(hfac)(L)]·CHCl ((3)·CHCl), [Dy(hfac)(L)][Dy(hfac)(HO)] (4), [Dy(hfac)(OH)(L)] (5), [Yb(tta)(L)] (6) and [Ln(hfc)(L)] (Ln = Dy (7, 7) and Yb (8, 8)) (where hfac = 1,1,1,5,5,5-hexafluoroacetylacetonate, tta = 2-thenoyltrifluoroacetylacetonate, hfc = 3-(heptafluoropropylhydroxymethylene-(±)-camphorate and L = 4-methylbipyrimidine-2--oxide ligand)) were isolated and characterized by single crystal and powder X-ray diffraction. All the Yb(iii) based-complexes demonstrate a slow relaxation of the magnetization under an applied DC field, which occurs through a Raman process and an additional Orbach process for 6. The two Dy(iii) dinuclear complexes 3 and 7 display slow magnetic relaxation in a zero applied DC field, whereas complex 4, which is similar to 3 with co-crystallization of Dy(hfac)(HO), presents only a field-induced slow magnetic relaxation. Multi-field-induced single-molecule magnet (SMM) behaviour was observed for 7, while this was not the case for the Yb(iii) analogue 8.

Aliphatic dicarboxylate linker ligands are relatively understudied in the field of coordination networks (CNs) compared to their aromatic counterparts. Herein, we report the synthesis and characterisation of three nickel(ii) CNs comprised of mixed ditopic linkers, a linear ditopic imidazolyl ligand and three aliphatic dicarboxylates: [Ni(glu)(bimbz)], , [Ni(adi)(bimbz)(HO)], , and [Ni(muc)(bimbz)(HO)]·HO, (bimbz = 1,4-bis-(1-imidazol-1-yl)benzene, glu = glutaric acid, adi = adipic acid, muc = , -muconic acid). Single crystal X-ray diffraction studies reveal that this family of CNs is comprised from nickel-based octahedral 4-connected nodes linked through nickel-carboxylate and nickel-imidazole coordination bonds. The resulting structures can be described as non-interpenetrated square lattice, , ( and ) or 5-fold interpenetrated diamondoid, , () topology networks. A Cambridge Structural Database (CSD) mining study was conducted to evaluate the effect of node composition and structure on topology in 222 archived CNs of general formula [MLL'], [MLL'(HO)], [MLL'(HO)], [MLL'] (= "pillared paddlewheel") and (= "double-walled nets") where L = aliphatic dicarboxylate linker and L' = linear ditopic N-donor linker. In terms of prevalence, , , , and , respectively, were found to be the most common topologies for each of these compositions. These statistics suggest that aliphatic dicarboxylate linkers can have a profound and consistent effect on the resulting topology for certain node compositions. This is especially the case for "pillared paddlewheel" nets, which favour topology over the or "DMOF" topology that dominates for rigid linkers.

The hydrogen-bonding ability of XeF is an important factor influencing its chemical properties and reactivity, yet structurally characterised examples of hydrogen-bonded xenon fluorides remain rare. In this work, three salt cocrystals containing hydrogen-bonded xenon difluoride and hexafluoridoarsenate salts of protonated perfluoroamides-CFC(OH)NH[AsF]·XeF, CFC(OH)NH[AsF]·XeF, and CFC(OH)NH[AsF]·XeF-were synthesised and structurally characterised. Diverse hydrogen-bonding motifs were observed, and the first crystallographically characterised examples of N-H⋯FXeF hydrogen bonds are presented. In total, eleven new crystal structures are reported, including two perfluoroamides, three protonated and two hemiprotonated perfluoroamides, and one salt cocrystal containing an oxonium ion. The XeF-containing cocrystals demonstrate that XeF reliably functions as a hydrogen-bond acceptor and readily forms hydrogen-bonded cocrystals. These findings broaden the scope of noble-gas chemistry and highlight the potential of noble-gas fluorides for cocrystal formation.

ZnP, made from earth-abundant elements, is a promising candidate for thin-film solar cells but faces limitations due to difficulties in achieving n-type doping and its large lattice mismatch with commercial substrates and a high thermal expansion coefficient, causing defects and cracks. Graphene substrates can address these challenges thanks to its weak van der Waals interactions with ZnP allowing for mechanical transfer of the thin film and strain-free growth. This study compares five graphene substrates for quasi-van der Waals epitaxial (q-vdWe) growth of polycrystalline ZnP thin films using molecular beam epitaxy. Surface features like steps and wrinkles on graphene were identified as main nucleation sites for ZnP, provided the graphene has minimal point defects. The highest-quality thin films, with the largest grain sizes, were grown on H-CVD graphene on the Si-face of 6H-SiC, featuring solely terraces of atomic height. All substrates showed comparable growth windows for crystalline ZnP, with higher growth temperatures improving crystal quality, as indicated by enhanced photoluminescence. Cryo-cathodoluminescence measurements revealed spatially localized sub-bandgap emissions, potentially linked to localized strain fields at grain boundaries of up to ±3% as identified by cross-sectional transmission electron microscopy. This work provides insights into advantages and drawbacks of utilising q-vdWe to produce ZnP thin films for solar cell applications and highlights the effects of graphene substrate choice and growth parameters on ZnP film quality.

Porous coordination networks (PCNs) such as metal-organic frameworks are of topical interest thanks to their potential utility as sorbents for gas and vapour separations and/or storage. Interpenetrated PCNs, some of which offer promise for gas separations, remain relatively understudied in the context of water vapour sorption. Herein, we report an in-depth study of the water vapour sorption properties of a family of square lattice topology () PCNs of general formula (, M = Mn, Co, Ni, Zn, bipy = 4,4-bipyridine, squa = squarate). This family, several of which have been previously reported (Co, Ni, Mn), exist as rectangular grids that exhibit 2-fold inclined interpenetration, thereby forming ultramicroporous 3D supramolecular networks. Water vapour sorption studies of (M = Mn, Co, Ni, Zn) revealed S-shaped water vapour sorption isotherms with steps consistently below 10% relative humidity (RH) and little hysteresis. Such properties are pertinent to atmospheric water harvesting in arid regions (<30% RH). Water vapour humidity swing experiments (0-30% RH, 300 K) indicated hydrolytic stability for (M = Mn, Co, Ni, Zn) and retention of working capacity over 100 sorption/desorption cycles. (M = Mn, Co, Ni, Zn) also exhibit CO/N selectivity.

Discovery of their commercial potential gave rise to a massive implementation of zeolites in industrial (petro-)chemical processes. Their robustness and molecular scale porosity in combination with acidic and/or ion exchange properties makes zeolites nearly indispensable for most of these applications. This highlight explores the origins of zeolite porosity. As microporosity is an inherent feature of the formed topology, we emphasize the link with phase selection. For zeolites, phase selection is driven by competition between water and framework elements to coordinate with extra-framework species. This competition is important in the final product, where such coordinations provide thermodynamic stability, as well as in the crystallization medium where supermolecular structrures can play a templating role. Synthesis experiments using hydrated silicate ionic liquids show that limited water availability prompts the formation of less porous (or even dense) phases, while moderate hydration supports the development of more open frameworks. Understanding these interactions is key to deepening the insight into zeolite genesis and can guide strategies for tailoring material properties for industrial applications.

The coordination properties of a previously described fluorescence active ligand (), consisting of a coordinating unit (1-tetrazol-1-yl) and a fluorophore (4,4-difluoro-4-bora-3,4-diaza--indacene (BODIPY) derivative) towards Ag(i) were investigated. Additionally, the influence of different anions (BF , PF , PFO , ClO , ReO and NO ) and a co-ligand (CHCN) on the crystal structure formation and intramolecular interactions of the Ag(i) coordination compounds was studied. Beside structural investigations single crystal X-ray diffraction, bulk characterization of the coordination compounds was conducted in both solution and solid-state, including NMR (H, B, F, P and C), ATR-IR, UV-vis and photoluminescence spectroscopy as well as PXRD. Eleven distinct coordination compounds are reported, each falling into one of four classes: the first group (I) comprises of a mononuclear complex, whereas group (II) consists of dinuclear complexes with ligand bridged metal centers (Ag(i)) and weak intermetallic interactions (∼4 Å). Group (III) likewise includes dinuclear complexes, but the bridging mode was prevented and the Ag-Ag distance was reduced (∼3.2 Å) upon the addition of a co-ligand. Group (IV), a structurally diverse category consists of coordination polymers, which in some cases show even shorter intermetallic contacts (<3.1 Å). All investigated coordination compounds exhibit photoluminescence in the solid state, with structurally dependent emission maxima distinct from those of the ligand.

This study investigates the crystal structure and phase behaviour of two organofluorine aromatic compounds, -dichlorotetrafluorobenzene (-CFCl) and chloropentafluorobenzene (CFCl), with a focus on solid-state phase transitions and non-covalent interactions. The thermal and structural properties of these compounds were investigated using a combination of differential scanning calorimetry (DSC), variable-temperature powder X-ray diffraction (VT-PXRD), and single-crystal X-ray diffraction (SXD). While -CFCl showed no solid-state phase transitions, CFCl exhibited three solid-state phases, including a reversible solid-solid transition at low temperature and an elusive transition just below the melt. The phase II-III transition in CFCl is due to a change from twofold disorder to an antiferroelectric arrangement of the molecular dipole moment. Phase II of CFCl is isomorphous to the structure of -CFCl. A comparison of the different solid-state structures of mono- and -di-halide-substituted hexafluorobenzenes is given.

Precise control over the crystalline phase and crystallographic orientation within thin films of metal-organic frameworks (MOFs) is highly desirable. Here, we report a comparison of the liquid- and vapour-phase film deposition of two copper-dicarboxylate MOFs starting from an oriented metal hydroxide precursor. X-ray diffraction revealed that the vapour- or liquid-phase reaction of the linker with this precursor results in different crystalline phases, morphologies, and orientations. Pole figure analysis showed that solution-based growth of the MOFs follows the axial texture of the metal hydroxide precursor, resulting in heteroepitaxy. In contrast, the vapour-phase method results in non-epitaxial growth with uniplanar texture only.

This study describes the discovery of a unique ionic cocrystal of the active pharmaceutical ingredient (API) ponatinib hydrochloride (), and characterization using single-crystal X-ray diffraction (SCXRD) and solid-state NMR (SSNMR) spectroscopy. is a multicomponent crystal that features an unusual stoichiometry, with an asymmetric unit containing both monocations and dications of the ponatinib molecule, three water molecules, and three chloride ions. Structural features include (i) a charged imidazopyridazine moiety that forms a hydrogen bond between the ponatinib monocations and dications and (ii) a chloride ion that does not feature hydrogen bonds involving any organic moiety, instead being situated in a "square" arrangement with three water molecules. Multinuclear SSNMR, featuring high and ultra-high fields up to 35.2 T, provides the groundwork for structural interpretation of complex multicomponent crystals in the absence of diffraction data. A C CP/MAS spectrum confirms the presence of two crystallographically distinct ponatinib molecules, whereas 1D H and 2D H-H DQ-SQ spectra identify and assign the unusually deshielded imidazopyridazine proton. 1D Cl spectra obtained at multiple fields confirm the presence of three distinct chloride ions, with density functional theory calculations providing key relationships between the SSNMR spectra and H⋯Cl hydrogen bonding arrangements. A 2D Cl → H D-RINEPT spectrum confirms the spatial proximities between the chloride ions, water molecules, and amine moieties. This all suggests future application of multinuclear SSNMR at high and ultra-high fields to the study of complex API solid forms for which SCXRD data are unavailable, with potential application to heterogeneous mixtures or amorphous solid dispersions.

We explore the role and nature of torsional flexibility of carboxylate-benzene links in the structural chemistry of metal-organic frameworks (MOFs) based on Zn and benzenedicarboxlyate (bdc) linkers. A particular motivation is to understand the extent to which such flexibility is important in stabilising the unusual topologically aperiodic phase known as TRUMOF-1. We compare the torsion angle distributions of TRUMOF-1 models with those for crystalline Zn/1,3-bdc MOFs, including a number of new materials whose structures we report here. We find that both periodic and aperiodic Zn/1,3-bdc MOFs sample a similar range of torsion angles, and hence the formation of TRUMOF-1 does not require any additional flexibility beyond that already evident in chemically-related crystalline phases. Comparison with Zn/1,4-bdc MOFs does show, however, that the lower symmetry of the 1,3-bdc linker allows access to a broader range of torsion angles, reflecting a greater flexibility of this linker.

Self-assembling peptides are of huge interest for biological, medical and nanotechnological applications. The enormous chemical variety that is available from the 20 amino acids offers potentially unlimited peptide sequences, but it is currently an issue to predict their supramolecular behavior in a reliable and cheap way. Herein we report a computational method to screen and forecast the aqueous self-assembly propensity of amyloidogenic pentapeptides. This method was found also as an interesting tool to predict peptide crystallinity, which may be of interest for the development of peptide based drugs.

Bifunctional N-donor carboxylate linkers generally afford and topology coordination networks of general formula ML that are based upon the MN(CO) molecular building block (MBB). Herein, we report on a new N-donor carboxylate linker, β-(3,4-pyridinedicarboximido)propionate (PyImPr), which afforded Cd(PyImPr) reaction of PyImPrH with Cd(acetate)·2HO. We observed that, depending upon whether Cd(PyImPr) was prepared by layering or solvothermal methods, 2D or 3D supramolecular isomers, respectively, of Cd(PyImPr) were isolated. Single crystal X-ray diffraction studies revealed that both supramolecular isomers are comprised of the same carboxylate bridged rod building block, RBB. We were interested to determine if the ethylene moiety of PyImPr could enable structural flexibility. Indeed, open-to-closed structural transformations occurred upon solvent removal for both phases, but they were found to be irreversible. A survey of the Cambridge Structural Database (CSD) was conducted to analyse the relative frequency of RBB topologies in related ML coordination networks in order to provide insight from a crystal engineering perspective.

Metal-organic frameworks bearing coordinatively unsaturated Mg(II) sites are promising materials for gas storage, chemical separations, and drug delivery due to their low molecular weights and lack of toxicity. However, there remains a limited number of such MOFs reported in the literature. Herein, we investigate the gas sorption properties of the understudied framework Mg(-dobdc) (dobdc = 4,6-dioxido-1,3-benzenedicarboxylate) synthesized under both solvothermal and mechanochemical conditions. Both materials are found to be permanently porous, as confirmed by 77 K N adsorption measurements. In particular, Mg(-dobdc) synthesized under mechanochemical conditions using exogenous organic base displays one of the highest capacities reported to date (6.14 mmol/g) for CO capture in a porous solid under simulated coal flue gas conditions (150 mbar, 40 °C). As such, mechanochemically synthesized Mg(-dobdc) represents a promising new framework for applications requiring high gas adsorption capacities in a porous solid.

The tetratopic 1,4-bis(2-phenylethoxy)-2,5-bis(3,2':6',3''-terpyridin-4'-yl)benzene (1) and 1,4-bis(3-phenylpropoxy)-2,5-bis(3,2':6',3''-terpyridin-4'-yl)benzene (2) ligands have been prepared and fully characterised. Combination of ligand 1 or 2 and [M(hfacac)]·HO (M = Cu, = 1; M = Zn, = 2) under conditions of crystal growth by layering led to the formation of [Cu(hfacac)(1)] ·3.6(1,2-ClCH)·2CHCl, [Zn(hfacac)(1)] ·MeCH·1.8CHCl, [Cu(hfacac)(2)] ·MeCH·2HO, [Cu(hfacac)(2)] ·2.8CHCl and [Cu(hfacac)(2)] ·2(1,2-ClCH)·0.4CHCl·0.5HO. For each compound, single-crystal X-ray analysis revealed the assembly of a planar (4,4)-net in which the tetratopic ligands 1 or 2 define the nodes. The metal centres link two different bis(3,2':6',3''-tpy) ligands the outer pyridine rings; whereas copper(ii) has N-donors in a -arrangement, zinc(ii) has them in . This difference between the copper(ii) and zinc(ii) coordination polymers modifies the architecture of the assembly without changing the underlying (4,4)-network.

The performance of zeolitic imidazolate frameworks (ZIFs) as protective hosts for proteins in drug delivery or biocatalysis strongly depends on the type of crystalline phase used for the encapsulation of the biomacromolecule (biomacromolecule@ZIF). Therefore, quantifying the different crystal phases and the amount of amorphous content of ZIFs is becoming increasingly important for a better understanding of the structure-property relationship. Typically, crystalline ZIF phases are qualitatively identified from diffraction patterns. However, accurate phase examinations are time-consuming and require specialized expertise. Here, we propose a calibration procedure (internal standard ZrO) for the rapid and quantitative analysis of crystalline and amorphous ZIF phases from diffraction patterns. We integrated the procedure into a user-friendly web application, named ZIF Phase Analysis, which facilitates ZIF-based data analysis. As a result, it is now possible to quantify i) the relative amount of various common crystal phases (sodalite, diamondoid, ZIF-CO-1, ZIF-EC-1, U12 and ZIF-L) in biomacromolecule@ZIF biocomposites based on Zn and 2-methylimidazole (HmIM) and ii) the crystalline-to-amorphous ratio. This new analysis tool will advance the research on ZIF biocomposites for drug delivery and biocatalysis.

The rapid increase in the number and variety of metal organic frameworks (MOFs) and covalent organic frameworks (COFs) has led to groundbreaking applications in the field of materials science and engineering. New MOF/COF hybrids combine the outstanding features of MOF and COF structures, such as high crystallinities, large surface areas, high porosities, the ability to decorate the structures with functional groups, and improved chemical and mechanical stabilities. These new hybrid materials offer promising performances for a wide range of applications including catalysis, energy storage, gas separation, and nanomedicine. In this highlight, we discuss the recent advancements of MOF/COF hybrids as next generation materials for energy and biomedical applications with a special focus on the use of computational tools to address the opportunities and challenges of using MOF/COF hybrids for various applications.

This paper details the first dedicated production of homogeneous nanocrystalline particles of mixed actinide oxide solid solutions containing americium. The target compositions were UPuAmO, UAmO and UAmO. After successful hydrothermal synthesis and chemical characterisation, the nanocrystals were sintered and their structure and behaviour under self-irradiation were studied by powder XRD. Cationic charge distribution of the as-prepared nanocrystalline and sintered UAmO materials was investigated applying U M and Am M edge high energy resolution XANES (HR-XANES). Typical oxidation states detected for the cations are U(iv)/U(v) and Am(iii)/Am(iv). The measured crystallographic swelling was systematically smaller for the as-synthesised nanoparticles than the sintered products. For sintered pellets, the maximal volumetric swelling was about 0.8% at saturation, in line with literature data for PuO, AmO, (U,Pu)O or (U,Am)O.

[This corrects the article DOI: 10.1039/C4CE02347A.].

The synthesis and X-ray structural study of the new family of compounds BaFeClO with tunable structural modulation are reported. The framework of the structure has the BaFeO composition, with open hexagonal channels extending along the -axis. The channels are filled with linear [Ba-Cl-Ba] triplets. The oxygen stoichiometry and the oxidation state of iron both are controlled by the redox conditions during crystal preparation. The modulation of the crystal structure arises from the distribution of the oxygen atoms in the framework and iron coordination polyhedra are a combination of FeO-tetrahedra, FeO-bipyramids, and FeO-octahedra. The structure modulation also originates from the ordered or disordered distribution of the [Ba-Cl-Ba] triplets filling the channels which is also affected by the conditions of the thermal treatment of the crystals. The structure investigation reveals a composition variation from BaFeClO ( = 0), in which Fe exhibits a 3+ oxidation state, to BaFeClO ( = 1.5) with the framework built exclusively of FeO tetrahedra.

Corrosion is a major concern for many industries, as corrosive environments can induce structural and morphological changes that lead to material dissolution and accelerate material failure. The progression of corrosion depends on nanoscale morphology, stress, and defects present. Experimentally monitoring this complex interplay is challenging. Here we implement Bragg coherent X-ray diffraction imaging (BCDI) to probe the dissolution of a Co-Fe alloy microcrystal exposed to hydrochloric acid (HCl). By measuring five Bragg reflections from a single isolated microcrystal at ambient conditions, we compare the full three-dimensional (3D) strain state before corrosion and the strain along the [111] direction throughout the corrosion process. We find that the strained surface layer of the crystal dissolves to leave a progressively less strained surface. Interestingly, the average strain closer to the centre of the crystal increases during the corrosion process. We determine the localised corrosion rate from BCDI data, revealing the preferential dissolution of facets more exposed to the acid stream, highlighting an experimental geometry effect. These results bring new perspectives to understanding the interplay between crystal strain, morphology, and corrosion; a prerequisite for the design of more corrosion-resistant materials.