Detonation of fulminating gold produces heterogeneous gold nanoparticles.

Fulminating gold, the first high-explosive compound to be discovered, disintegrates into a mysterious cloud of purple smoke, the nature of which has been speculated upon since its discovery in the 15th century. In this work, we show that the colour of the smoke is due to the presence of gold nanoparticles.

Morphological Control of Crystalline Savolitinib via the Volatile Deep Eutectic Solvent Technique.

Savolitinib is a compound that can crystallize in an undesirable, high aspect ratio needle morphology. This morphology type may cause issues in downstream processing. This paper demonstrates a unique method to alter the crystal morphology of savolitinib to make it more processable, resulting in the active pharmaceutical ingredient (API) crystallizing out in considerably more processable stellates.

New and Unforeseen Crystal Growth Processes for a Metal Oxide.

The synthesis of corundum (α-AlO) via a layered AlO-MoO system was directly observed for the first time. This revealed a new crystal growth process with three key features: (1) the formation of an Al(MoO) intermediate layer through a solid-solid interaction in the temperature range of ∼705-860 °C; (2) the melting of the Al(MoO) layer between approximately 870 and 890 °C; and (3) the decomposition of Al(MoO) to corundum between 950 and 1100 °C. This molten intermediate decomposition (MIND) mechanism produced corundum, which was light bluish-gray in color and was defined in CIE () color space as = 76.

Improved air-stability and conductivity in the 75LiS·25PS solid-state electrolyte system: the role of LiPS.

Doping modification is regarded as a simple and effective method for increasing the ionic conductivity and air stability of solid state electrolytes. In this work, a series of (100-)(0.75LiS·0.

Crystal structures, Hirshfeld analysis, and energy framework analysis of two differently 3'-substituted 4-methylchalcones: 3'-(N=CHCH-p-CH)-4-methylchalcone and 3'-(NHCOCH)-4-methylchalcone.

Two crystal structures of chalcones, or 1,3-diarylprop-2-en-1-ones, are presented; both contain a p-methyl substitution on the 3-Ring, but differ with respect to the m-substitution on the 1-Ring. Their systematic names are (2E)-3-(4-methylphenyl)-1-(3-{[(4-methylphenyl)methylidene]amino}phenyl)prop-2-en-1-one (CHNO) and N-{3-[(2E)-3-(4-methylphenyl)prop-2-enoyl]phenyl}acetamide (CHNO), which are abbreviated as 3'-(N=CHCH-p-CH)-4-methylchalcone and 3'-(NHCOCH)-4-methylchalcone, respectively. Both chalcones represent the first reported acetamide-substituted and imino-substituted chalcone crystal structures, adding to the robust library of chalcone structures within the Cambridge Structural Database.

Rapid sol-gel synthesis of honeycomb-layered NaNiBiO and orthorhombic NaCaBiO.

The AMM'O type materials NaCaBiO and NaNiBiO were successfully synthesised through two sol-gel techniques - a method based on a natural deep eutectic solvent, and a biopolymer-mediated synthesis. The materials were analysed using Scanning Electron Microscopy to determine if there was a difference in final morphology between the two methods, and it was found that the natural deep eutectic solvent method resulted in a more porous morphology. For both materials, the optimum dwell temperature was found to be 800 °C, which in the case of NaCaBiO was a much less energy-intensive synthesis process than its seminal solid-state synthesis.

True molecular conformation and structure determination by three-dimensional electron diffraction of PAH by-products potentially useful for electronic applications.

The true molecular conformation and the crystal structure of benzo[e]dinaphtho[2,3-a;1',2',3',4'-ghi]fluoranthene, 7,14-diphenylnaphtho[1,2,3,4-cde]bisanthene and 7,16-diphenylnaphtho[1,2,3,4-cde]helianthrene were determined ab initio by 3D electron diffraction. All three molecules are remarkable polycyclic aromatic hydrocarbons. The molecular conformation of two of these compounds could not be determined via classical spectroscopic methods due to the large size of the molecule and the occurrence of multiple and reciprocally connected aromatic rings.

Synthesis of porous high-temperature superconductors a melamine formaldehyde sacrificial template.

Nanostructured high-temperature superconductors YBaCuO and BiSrCaCuO were synthesised using a melamine formaldehyde sponge as a sacrificial template, three solution-based approaches. In the case of YBaCuO , a modified Pechini method produced a material with a superconducting transition at 92 K and a specific surface area of 4.22 m g.

Determining nanorod dimensions in dispersion with size anisotropy nanoparticle tracking analysis.

Control over nanorod dimensions is critical to their application, requiring fast, robust characterisation of their volume and aspect ratio whilst in their working medium. Here, we present an extension of Nanoparticle Tracking Analysis which determines the aspect ratio of nanoparticles from the polarisation state of scattered light in addition to a hydrodynamic diameter from Brownian motion. These data, in principle, permit the determination of nanorod dimensions of any composition using Nanoparticle Tracking Analysis.

Laser-induced convection shifts size distributions in nanoparticle tracking analysis.

This work discusses the effects of increasing laser power on the size data derived from NTA for particles of known size and scatterers in solutions of flufenamic acid in ethanol. We find that whilst a higher laser power reveals more particles as expected, their residence time changes due to laser-induced convection. This reduced residence time decreases the number of tracks available for individual particle size determination, shifting the size distribution to smaller values.

Structure determination, thermal stability and dissolution rate of δ-indomethacin.

The structure solution of the δ-polymorph of indomethacin was obtained using three-dimensional electron diffraction. This form shows a significantly enhanced dissolution rate compared with the more common and better studied α- and γ-polymorphs, indicating better biopharmaceutical properties for medicinal applications. The structure was solved in non-centrosymmetric space group P2 and comprises two molecules in the asymmetric unit.

Improved photodegradation of anionic dyes using a complex graphitic carbon nitride and iron-based metal-organic framework material.

Introducing heterostructures to graphitic carbon nitrides (g-CN) can improve the activity of visible-light-driven catalysts for the efficient treatment of multiple toxic pollutants in water. Here, we report for the first time that a complex material can be constructed from oxygen-doped g-CN and a MIL-53(Fe) metal-organic framework using facile hydrothermal synthesis and recycled polyethylene terephthalate from plastic waste. The novel multi-walled nanotube structure of the O-g-CN/MIL-53(Fe) composite, which enables the unique interfacial charge transfer at the heterojunction, showed an obvious enhancement in the separation efficiency of the photochemical electron-hole pairs.

3D Electron Diffraction Structure Determination of Terrylene, a Promising Candidate for Intermolecular Singlet Fission.

Herein we demonstrate the prowess of the 3D electron diffraction approach by unveiling the structure of terrylene, the third member in the series of peri-condensed naphthalene analogues, which has eluded structure determination for 65 years. The structure was determined by direct methods using electron diffraction data and corroborated by dispersion-inclusive density functional theory optimizations. Terrylene crystalizes in the monoclinic space group P2 /a, arranging in a sandwich-herringbone packing motif, similar to analogous compounds.

Structural effects of halogen bonding in iodochalcones.

The structures of three iodochalcones, functionalized with fluorine or a nitro group, have been investigated to explore the impact of different molecular electrostatic distributions on the halogen bonding within each crystal structure. The strongly withdrawing nitro group presented a switch of the halogen bond from a lateral to a linear motif. Surprisingly, this appears to be influenced by a net positive shift in charge distribution around the lateral edges of the σ-hole, making the lateral I.

A new olanzapine cocrystal obtained from volatile deep eutectic solvents and determined by 3D electron diffraction.

A previously unknown cocrystal of olanzapine and phenol was identified from a volatile deep eutectic solvent as the intermediate species in the crystallization of olanzapine. This new nanocrystalline phase was investigated by electron diffraction, powder X-ray diffraction and differential scanning calorimetry. The structure was determined by simulated annealing using 3D electron diffraction data and confirmed using DFT-D optimizations.

Crystal structures of three functionalized chalcones: 4'-di-methyl-amino-3-nitro-chalcone, 3-di-methyl-amino-3'-nitrochalcone and 3'-nitro-chalcone.

The structure of three functionalized chalcones (1,3-di-aryl-prop-2-en-1-ones), containing combinations of nitro and di-methyl-amino functional groups, are presented, namely, 1-[4-(di-methyl-amino)-phen-yl]-3-(3-nitro-phen-yl)prop-2-en-1-one, CHNO, Gp8m, 3-[3-(di-methyl-amino)-phen-yl]-1-(3-nitro-phen-yl)prop-2-en-1-one, CHNO, Hm7m and 1-(3-nitro-phen-yl)-3-phenyl-prop-2-en-1-one, CHNO, Hm1-. Each of the mol-ecules contains bonding motifs seen in previously solved crystal structures of functionalized chalcones, adding to the large dataset available for these small organic mol-ecules. The structures of all three of the title compounds contain similar bonding motifs, resulting in two-dimensional planes of mol-ecules formed C-H⋯O hydrogen-bonding inter-actions involving the nitro- and ketone groups.

Crystal structure and Hirshfeld analysis of 3'-bromo-4-methyl-chalcone and 3'-cyano-4-methyl-chalcone.

Two crystal structures of chalcones, or 1,3-di-aryl-prop-2-en-1-ones, are presented; both contain a methyl substitution on the 3-Ring, but differ on the 1-Ring, bromo cyano. The compounds are 3'-bromo-4-methyl-chalcone [systematic name: 1-(2-bromo-phen-yl)-3-(4-methyl-phen-yl)prop-2-en-1-one], CHBrO, and 3'-cyano-4-methyl-chalcone {systematic name: 2-[3-(4-methyl-phen-yl)prop-2-eno-yl]benzo-nitrile}, CHNO. Both chalcones meaningfully add to the large dataset of chalcone structures.

The solubility and stability of heterocyclic chalcones compared with trans-chalcone.

Heterocyclic chalcones are a recently explored subgroup of chalcones that have sparked interest due to their significant antibacterial and antifungal capabilities. Herein, the structure and solubility of two such compounds, (E)-1-(1H-pyrrol-2-yl)-3-(thiophen-2-yl)prop-2-en-1-one and (E)-3-phenyl-1-(1H-pyrrol-2-yl)prop-2-en-1-one, are assessed. Single crystals of (E)-1-(1H-pyrrol-2-yl)-3-(thiophen-2-yl)prop-2-en-1-one were grown, allowing structural comparisons between the heterocyclic chalcones and (2E)-1,3-diphenylprop-2-en-1-one, trivially known as trans-chalcone.

Metastable crystalline phase formation in deep eutectic systems revealed by simultaneous synchrotron XRD and DSC.

The phase behaviour of various deep eutectic systems was analysed using concurrent synchrotron powder X-ray diffraction and differential scanning calorimetry. Deep eutectic systems containing the pharmaceuticals metacetamol, 2-ethoxybenzamide or benzamide as binary mixtures with phenol revealed new crystalline phases melting either before or with crystals of phenol, highlighting their lower stabilities. Furthermore, in the phenol : 2-ethoxybenzamide system it was shown that multiple metastable phases can form, highlighting the potential for the separation of a hierarchy of crystal structures with differing stabilities from eutectic systems.

Size-dependent melting point depression of nickel nanoparticles.

We investigate the phase-transition behaviour of nickel nanoparticles (3-6 nm) dynamic TEM. The nanoparticles were synthesized within a reverse microemulsion and then monitored dynamic TEM simultaneously while undergoing controlled heating. The size-dependent melting point depression experimentally observed is compared with, and is in good agreement with existing thermodynamic and molecular dynamic predictions.

Visualising early-stage liquid phase organic crystal growth via liquid cell electron microscopy.

Here, we show that the development of nuclei and subsequent growth of a molecular organic crystal system can be induced by electron beam irradiation by exploiting the radiation chemistry of the carrier solvent. The technique of Liquid Cell Electron Microscopy was used to probe the crystal growth of flufenamic acid; a current commercialised active pharmaceutical ingredient. This work demonstrates liquid phase electron microscopy analysis as an essential tool for assessing pharmaceutical crystal growth in their native environment while giving insight into polymorph identification of nano-crystals at their very inception.

Crystal structure and Hirshfeld surface analysis of ()-3-(3-iodo-phen-yl)-1-(4-iodo-phen-yl)prop-2-en-1-one.

The title compound, CHIO, is a halogenated chalcone formed from two iodine substituted rings, one -substituted and the other -substituted, linked through a prop-2-en-1-one spacer. In the mol-ecule, the mean planes of the 3-iodo-phenyl and the 4-iodo-phenyl groups are twisted by 46.51 (15)°.

An experimental and computational study into the crystallisation propensity of 2nd generation sulflower.

The crystallisation propensity of the newly synthesised molecule persulfurated coronene has been investigated through a number of experimental methods. Electrostatic potential calculations and multi-molecular optimisations show that face-face interactions are far more favorable than edge-face interactions, severely restricting the ability of the molecule to crystallise.

The Crystal Structure of Orthocetamol Solved by 3D Electron Diffraction.

Orthocetamol is a regioisomer of the well-known pain medication paracetamol and a promising analgesic and an anti-arthritic medicament itself. However, orthocetamol cannot be grown as single crystals suitable for X-ray diffraction, so its crystal structure has remained a mystery for more than a century. Here, we report the ab-initio structure determination of orthocetamol obtained by 3D electron diffraction, combining a low-dose acquisition method and a dedicated single-electron detector for recording the diffracted intensities.

Lamotrigine ethanol monosolvate.

Lamotrigine is an active pharmaceutical ingredient used as a treatment for epilepsy and psychiatric disorders. Single crystals of an ethano-late solvate, CHClN·CHOH, were produced by slow evaporation of a saturated solution from anhydrous ethanol. Within the crystal structure, the lamotrigine mol-ecules form dimers through N-H⋯N hydrogen bonds involving the amine N atoms in the position of the triazine group.