We demonstrate a simple method for real-time monitoring of mechanochemical synthesis metal–organic frameworks, by measuring changes in pressure gas produced the reaction.

We report a strategy for structure determination of organic materials in which complete solid-state nuclear magnetic resonance (NMR) spectral data is utilized within the context from powder X-ray diffraction (XRD) data. Following crystal XRD data, first-principles density functional theory-based techniques GIPAW approach are exploited to calculate NMR structure, followed by careful scrutiny agreement with experimental The successful application this demonstrated 1:1 cocrystal indomethacin...

A multi-technique strategy reveals a new hydrogen-bonding motif for 2′-deoxyguanosine derivative.

Abstract During the last 75 years, crystal structures have been reported for 19 of 20 directly encoded proteinogenic amino acids in their natural (enantiomerically pure) form. The structure is now final member this set: L ‐lysine. As crystalline ‐lysine has a strong propensity to incorporate water under ambient atmospheric conditions form hydrate phase, pure (non‐hydrate) phase can be obtained only by dehydration rigorously anhydrous conditions, resulting microcrystalline powder sample. For...

We report the crystal structure of L-arginine, one last remaining natural amino acids for which has never been determined; determination was carried out directly from powder X-ray diffraction (XRD) data, exploiting direct-space genetic algorithm technique solution followed by Rietveld refinement.

Given the importance of phenomenon polymorphism from both fundamental and applied perspectives, there is considerable interest in discovery new systems that exhibit abundant polymorphism. In present article, preparation strategies structural properties three polymorphs (denoted Forms III, IV, V) m-aminobenzoic acid (m-ABA) are reported, elevating this system to rare class polymorphic with at least five known polymorphs. The crystal structures have been determined directly powder X-ray...

Abstract A new in‐situ NMR strategy (termed CLASSIC NMR) for mapping the evolution of crystallization processes is reported, involving simultaneous measurement both liquid‐state and solid‐state spectra as a function time. This combined allows complementary information to be obtained on solid liquid phases during process. In particular, proceeds (monitored by NMR), solution state becomes more dilute, leading changes in solution‐state speciation modes molecular aggregation solution, which are...

Crystallization plays an important role in many areas, and to derive a fundamental understanding of crystallization processes, it is essential understand the sequence solid phases produced as function time. Here, we introduce new NMR strategy for studying time evolution which crystallizing system quenched rapidly low temperature at specific points during crystallization. The crystallized phase present within resultant "frozen solution" may be investigated detail using range sophisticated...

The application of<italic>in situ</italic>techniques for investigating crystallization processes promises to yield significant new insights into fundamental aspects of science. With this motivation, we recently developed a new<italic>in situ</italic>solid-state NMR technique that exploits the ability selectively detect solid phase in heterogeneous solid–liquid systems (of type exist during from solution), with liquid “invisible” measurement. As consequence, allows first particles produced be...

This paper explores the capability of using DFT-D ab initio random structure searching (AIRSS) method to generate crystal structures organic molecular materials, focusing on a system (m-aminobenzoic acid; m-ABA) that is known from experimental studies exhibit abundant polymorphism. Within structural constraints selected for AIRSS calculations (specifically, centrosymmetric with Z = 4 zwitterionic m-ABA molecules), shown successfully two polymorphs (form III and form IV) have these features....

In this work, a comprehensive account of the authors' synthetic efforts to prepare borazino-doped hexabenzocoronenes by using Friedel-Crafts-type electrophilic aromatic substitution is reported. Hexafluoro-functionalized aryl borazines, bearing an ortho fluoride leaving group on each N- and B-aryl rings, was shown lead cascade-type events in stepwise C-C bond formation, giving higher yields borazinocoronenes than those obtained with borazine precursors groups at positions substituents. By...

We report the discovery of new polymorphic forms solids by exploiting a solid-state NMR technique that has been developed for in situ monitoring evolution crystallization processes. The capability to reveal existence molecular is illustrated two polymorphs methyldiphenylphosphine oxide and solid form 1,10-dihydroxydecane/urea system.

Abstract A new polymorph of l ‐tryptophan was prepared through crystallization from the gas phase, with structure determination carried out directly powder XRD data augmented by periodic DFT‐D calculations. The (denoted β) and previously reported α) are both based on alternating hydrophilic hydrophobic layers, but substantially different hydrogen‐bonding arrangements. β exhibits energetically favourable 2‐ 2 arrangement, which is unprecedented for amino acids aromatic side chains. specific...

Solid-state NMR spectroscopy is a well-established and versatile technique for studying the structural dynamic properties of solids, there considerable potential to exploit power versatility solid-state in-situ studies chemical processes. However, number technical challenges are associated with adapting this studies, depending on process interest. Recently, an strategy monitoring evolution crystallization processes has been developed proven be promising approach identifying sequence distinct...

The crystal structure of l-lysine was reported very recently and represented the final member set 20 directly encoded proteinogenic amino acids to have a enantiomerically pure form determined. Under ambient conditions, has strong propensity undergo hydration by incorporation water into structure, dehydration under rigorously dry conditions is required obtain anhydrous l-lysine. In present paper, we explore l-lysine, which led identification characterization hemihydrate phase monohydrate...

Until recently it was thought that the only optical function of pteridines in biology to act as light-absorbing pigments, but a recent report by some us revealed crystalline isoxanthopterin is reflector eyes decapod crustaceans. Here, we formation synthetically from polar dimethyl sulfoxide solvent, with X-ray diffraction analysis revealing crystal structure different biogenic isoxanthopterin. The new polymorph determined two independent ways. In one approach, generated and optimized using...

Recently, a second crystalline polymorph (Form II) of racemic ibuprofen was reported to be obtained by crystallization from the supercooled liquid state. The procedure involved temperature schedule that included requirement quench sample (168 K) significantly below glass-transition (228 followed annealing at (typically 258 above temperature. In present work, we show (by differential scanning calorimetry and in situ, variable-temperature powder X-ray diffraction) Form II can prepared...

Among the 20 directly encoded proteinogenic amino acids, arginine is one of five remaining cases for which crystal structure a racemic crystalline phase has not yet been reported. In this paper, dl-arginine determined by exploiting modern methods analysis powder X-ray diffraction data, in conjunction with periodic DFT-D calculations. The provides interesting contrasts and comparisons to that enantiomerically pure (l-arginine), was also recently from data.

Abstract With the growing realization that crystallization processes may evolve through a sequence of different solid forms, including amorphous precursor phases, development suitable in‐situ experimental probes is essential for comprehensively mapping time‐evolution such processes. Here we demonstrate CLASSIC NMR (Combined Liquid‐ And Solid‐State In‐situ Crystallization NMR) strategy powerful technique revealing transitory existence phases during processes, applying this to study dl...

Abstract A new in‐situ NMR strategy (termed CLASSIC NMR) for mapping the evolution of crystallization processes is reported, involving simultaneous measurement both liquid‐state and solid‐state spectra as a function time. This combined allows complementary information to be obtained on solid liquid phases during process. In particular, proceeds (monitored by NMR), solution state becomes more dilute, leading changes in solution‐state speciation modes molecular aggregation solution, which are...

Phase transitions in crystalline molecular solids have important implications the fundamental understanding of materials properties and development applications. Herein, we report solid-state phase transition behavior 1-iodoadamantane (1-IA) investigated using a multi-technique strategy [synchrotron powder X-ray diffraction (XRD), single-crystal XRD, NMR, differential scanning calorimetry (DSC)], which reveals complex on cooling from ambient temperature to ca. 123 K subsequent heating...

Two multicomponent crystalline phases of (S)-ibuprofen and l-proline with 1:1 stoichiometry are reported, specifically a nonsolvate phase (Ibu-Pro) quarter-hydrate (Ibu-Pro-QH). Ibu-Pro was prepared only by solid-state mechanochemical synthesis, while Ibu-Pro-QH obtained both solution-state crystallization mechanochemistry. The crystal structures were determined directly from powder X-ray diffraction (XRD) data, structure solution carried out using the direct-space strategy (implemented...

Abstract In situ solid‐state NMR spectroscopy is exploited to monitor the structural evolution of a glycine/water glass phase formed on flash cooling an aqueous solution glycine, with range modern methods applied elucidate properties solid phases present. The shown crystallize into intermediate phase, which then transforms β polymorph glycine. Our in results fully corroborate identity crystalline as glycine dihydrate, was first proposed only very recently.

Abstract During the last 75 years, crystal structures have been reported for 19 of 20 directly encoded proteinogenic amino acids in their natural (enantiomerically pure) form. The structure is now final member this set: L ‐lysine. As crystalline ‐lysine has a strong propensity to incorporate water under ambient atmospheric conditions form hydrate phase, pure (non‐hydrate) phase can be obtained only by dehydration rigorously anhydrous conditions, resulting microcrystalline powder sample. For...