CrystEngComm最新文献

A detailed understanding and investigation of mismatched bases in non-B DNA structures can help reveal the pathogenesis of hereditary genetic diseases and provide a theoretical foundation for the development of gene therapy technologies. Accordingly, this study successfully designed and synthesized three nucleotide-based assemblies using guanosine 5′-monophosphate (GMP) as a building block. The synthesis leveraged a synergistic assembly strategy involving transition metal ions and the auxiliary ligand bpe, controlled by pH modulation. The assemblies are: {[M(GMP)(bpe)(H₂O)₃]·9H₂O}_n (M = Mn(II), Ni(II)) (1 and 2) and (HGMP)₂(H₂bpe)·7H₂O (3) (bpe = 1,2-bis(4-pyridyl)ethylene). Comprehensive characterization of 1–3 was conducted through infrared spectroscopy (IR), ultraviolet-visible spectroscopy (UV-vis), X-ray powder diffraction (PXRD) and single-crystal X-ray diffraction. Crystallographic studies revealed that 1 and 2 exist as coordination polymers, while 3 forms an ionic co-crystal. In 3, the bpe ligand serves as a “scaffolding” through multiple π–π stacking interactions, successfully constructing a guanine–guanine base mismatch pattern with high anti–anti glycosidic bond torsion angles. These validate that the strategy exhibits certain general applicability and effectiveness. Furthermore, combining single-crystal structure analysis and solid-state circular dichroism (CD) spectroscopy, the processes of chiral transfer, chiral induction, and chiral amplification in the three assemblies were investigated. It was found that in assembly 3 containing base mismatches, the system energy increases and the chiral signal undergoes a blue shift. This study not only develops a new assembly paradigm for nucleotide-based functional materials, but also provides important chemical model references for deepening the understanding of the molecular mechanism of base mismatches and designing targets in gene therapy.

Three chiral TADDOL (α,α,α,α′-tetraaryl-2,2-disubstituted 1,3-dioxolane-4,5-dimethanol) host molecules were employed to yield inclusion compounds with three isomers of methylcyclohexanones as guests. Although 4-methylcyclohexanone was not a chiral compound due to its internal symmetry, the other two isomers were racemates, and TADDOLs acted as potential resolving agents. The selectivity preference of the methylcyclohexanones for each host was established using solution nuclear magnetic resonance (NMR) spectroscopy, and the crystal structure of each host–guest compound was elucidated by single-crystal X-ray diffraction. The packing of the structures was analysed to explain the resulting resolution of the enantiomeric guests. The kinetics of decomposition were investigated for a representative TADDOL host.

The development of multicomponent composites with favorable morphology and superior architecture is crucial for designing advanced lithium-ion batteries. In this work, a MoS₂@C@SnS₂-NC material featuring a dual-carbon confinement structure and locally expanded interlayer spacing was constructed via a facile double-carbon coating process. In this multi-layered architecture, hollow MoS₂ serves as the substrate, significantly increasing the specific surface area. A robust carbon scaffold is established through dual-layer engineering: the inner carbon coating preserves tubular architecture against collapse and alleviates cycling-induced strain, while the outer carbon barrier concurrently suppresses polysulfide shuttle and reinforces structural durability, collectively ensuring electrode integrity. Furthermore, the integrated carbon network facilitates charge transport, leading to significantly enhanced electronic conductivity. During the growth of SnS₂, free dopamine molecules intercalate into the vertically aligned SnS₂ nanosheets, leading to localized expansion of the interlayer spacing. This greatly facilitates Li⁺ ion transport during charging and discharging, while the vertically aligned SnS₂ nanosheets provide abundant active sites for electrochemical reactions. Owing to its unique structural configuration, the MoS₂@C@SnS₂-NC composite retains a high reversible capacity of 1329.6 mAh g⁻¹ following 100 cycles at 0.1 A g⁻¹, delivers a substantial capacity of 647.7 mAh g⁻¹ even at 5.0 A g⁻¹, and maintains 1223.6 mAh g⁻¹ after 1000 cycles at a current density of 1 A g⁻¹. Furthermore, a MoS₂@C@SnS₂-NC//LiFePO₄ full cell was assembled to evaluate the practical application potential of the composite.

Stacking faults (SFs) are a kind of key defects governing the strength and ductility of multi-principal element alloys, but their stability and size-dependent effects remain unclear. Using molecular dynamics simulations, we revealed contrasting behaviors in Ni and CoCrNi. In Ni, the high stacking fault energy causes rapid annihilation of SFs, eliminating their strengthening contribution. In CoCrNi, the ultralow stacking fault energy stabilizes SFs, which persist as barriers to dislocation glide, leading to Hall–Petch-like strengthening. Crucially, a strong coupling between grain size (d) and SF spacing (λ) emerges: at d = 15 nm, grain refinement dominates and moderate SFs induce softening, whereas at d = 10 and d = 20 nm, dense SF networks markedly enhance the strength. These results reveal the atomic-scale mechanisms of SF-mediated strengthening and highlight the need for joint design of grain size and stacking fault distribution to the design of high-performance structural alloys.

In recent years, interest in 2D Janus materials has grown exponentially, particularly with regard to their applications in spintronics and optoelectronic devices. The defining feature of Janus materials is the ordered arrangement of different layer terminations – creating chemically distinct surfaces and an inherent out-of-plane polarity. Among the few known Janus materials, RhSeCl is particularly intriguing as a rare example of an intrinsic Janus compound. Owing to its exceptional chemical stability, RhSeCl offers a promising platform for exploring the physics related to the Janus-structure. However, synthesising large, high-quality crystals of this compound remains a significant challenge. Here, we report a novel synthetic pathway for growing crystals up to 6 mm in lateral size via a two-step self-selecting vapour growth reaction. We further present a comprehensive comparison of newly developed synthesis routes with all previously reported methods for RhSeCl. During these investigations, we identified a previously unreported impurity that forms in specific growth pathways and demonstrate how it can be avoided to obtain phase-pure few- and monolayer flakes. We showcase the reproducibility of the process to obtain high-quality, large single-crystals and flakes.

Macroscopic observation is an interesting topic in the field of non-classical crystallization. Because the glass transition temperature (T_g) of organic molecules is usually not high and can be further decreased by solvation, it is necessary to distinguish between supercooled liquids and amorphous solids during the crystallization process of organic molecules. The difference in the fluidity between these two phases makes it possible to distinguish them through a macroscopic observation. The transition process from a supercooled liquid precursor to the amorphous phase was observed without any additive during the evaporation crystallization process of valsartan in ethanol, as well as in the evaporation crystallization process of glucose in water, via visual inspection of fluidity and fluorescent probe method, and was also observed during the cooling crystallization process of valsartan in water via dissolution experiment and fluorescent probe method. More examples are needed to further refine the principle by which supercooled liquid precursors undergo a transformation to amorphous solids during the crystallization process of organic molecules.

In this study, we present a sustainable and scalable synthesis route for CALF-20 by employing zinc oxide (ZnO) as the zinc source, thereby eliminating the washing step that is required in previously reported methods. CALF-20 synthesized using ZnO exhibits CO₂ adsorption performance comparable to the literature while achieving complete crystallization within 3 h and reaching a high zinc-based yield of 97.1%. This environmentally benign process significantly reduces liquid waste generation and simplifies post-synthetic purification, offering strong potential for cost-effective, industrial-scale MOF production.

Ivacaftor (IVA) is a selective small-molecule potentiator used to treat cystic fibrosis in patients with certain genetic mutations. It is a BCS class II drug having poor aqueous solubility. The European Commission has granted orphan status to IVA. It is considered to be highly polymorphic based on literature, and several solvates have been reported in patents. To address the solubility and identify the most stable solid forms of IVA, crystal engineering strategies were employed in the present work to prepare new multicomponent solid forms, including cocrystals, salts, and solvates/hydrates. Eight new multicomponent solid forms of IVA were reported, along with the crystal structure of the polymorphic form of IVA (form-B). The eight new forms comprise one dihydrate form (IVA–2H₂O), two salt forms with hydrochloride and hydrobromide (IVA–HCl–EA and IVA–HBr–ACA), and five solvates with geraniol (GER), acetic acid (ACA, in two different stoichiometries), ethanolamine (ETA), and ethylene glycol (EGL). The solvates of monoacetic acid (IVA–ACA) and diacetic acid (IVA–DACA) were produced concomitantly during the crystallization experiments. IVA–GER crystallized as a monohydrate, whereas IVA–ETA and IVA–EGL crystallized in anhydrous forms. The prepared multicomponent solids displayed different conformations compared with the neutral IVA form-B; in particular, the protonated form exhibited twist conformations at the amide group. Four of the multicomponent solids were reproduced on the bulk scale and further characterized by thermal and spectroscopic analyses. Further, the solubility of the prepared multicomponent solids was evaluated in pH 1.2 and 6.8 buffers. All the prepared multicomponent solids showed enhanced solubility profiles in the buffer solutions. Notably, IVA–DACA exhibited a 2.5-fold increased solubility in the pH 1.2 buffer, while a 37-fold increase in solubility was observed for IVA–ETA in the pH 6.8 buffer. The IVA–GER solid form exhibited solid-state stability in both the pH media, while the remaining multicomponent solids were found to be unstable and converted to either their hydrate or solvate forms. The present study paves the way for modulating the solubility profile and solid-state stability of IVA via the crystal engineering strategy.

Electroplating is a widely used method for producing metal films, enabling the fabrication of metal foil materials with thicknesses below 20 μm. However, stripping ultra-thin metal films (<5 μm) from the cathode electrode plate remains challenging. Herein, this study reports an efficient electrodeposition process for producing easily peelable ultra-thin copper foil. The method first forms a nickel layer (<1 μm) via electrodeposition on the carrier copper foil. Subsequently, an adenine-based organic stripper is adsorbed onto the nickel layer via “Ni–N” interaction, with ultrasonic introduced during adsorption to enhance bonding effectiveness. DC electroplating of the copper foil on this modified substrate surface enables the production of ultra-thin copper foil as low as 3.5 μm. Research findings indicate that, compared to conventional copper foil preparation methods, this process effectively promotes “Ni–N” formation through ultrasonic treatment. The introduction of ultrasonic assistance during organic stripping layer adsorption results in lower peel strength for the ultra-thin copper foil electroplated on its surface. This facilitates easier, intact stripping of the ultra-thin copper foil while minimizing damage during stripping and storage. Ultra-thin copper foil produced via this method finds primary applications in integrated circuit (IC) packaging, chip packaging substrates, high-density interconnect (HDI) boards, and various high-end electronic products.

Peroxosolvates have found wide application as a source of hydrogen peroxide for bleaching and disinfecting agents in industry, medicine, household use and organic synthesis. The key problem in their industrial production from aqueous H₂O₂ solutions is the isomorphic substitution of H₂O₂ for H₂O during crystallization, driven by the similarity of hydrogen bonding networks. We report the first crystalline H₂O₂ adducts of primary, secondary and tertiary amine halides, synthesized from 5–97% w/w H₂O₂ solutions. These include peroxosolvates of aminoadamantane hydrochloride, ethylenediammonium dichloride, piperazinium dichloride and dibromide and triethylenediaminium dichloride, characterized by single crystal X-ray diffraction, elemental analysis, powder diffraction, IR spectroscopy and thermal analysis. Single-crystal XRD revealed structures stabilized by charge-assisted H-bond networks between H₂O₂, halide anions and organic ammonium cations. An unprecedented degree of isomorphic substitution of hydrogen peroxide by water, exceeding 50%, was discovered. The formation of peroxosolvates with H₂O₂/H₂O isomorphous substitution was observed for all organic diammonium dihalides, suggesting a potential general trend for such coformers. Solid-state DFT calculations indicate H₂O₂ forms stronger H-bonds than H₂O due to torsional adaptability to the distances between hydrogen bond acceptors. The synthesized peroxosolvates demonstrate relatively high thermal stability (up to 110–140 °C). The monoperoxosolvates of piperazinium dichloride and triethylenediaminium dichloride remain stable under ambient conditions, with a loss in relative H₂O₂ content of only 9.7% and 12.3%, respectively, over three months.