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In this study, we found that a recently discovered ECD-Raman effect dominated over the natural Raman optical activity in a series of atropisomeric naphthalenediimides, and we investigated the kind of information about the molecular structure that could be obtained from the spectra. The ECD-Raman effect is polarised Raman scattering modulated by electronic circular dichroism. We showed that the spectra significantly depended on the substitution of the solute and/or the change of the solvent. Moreover, the spectra could be well-predicted by the theory, thus providing an interesting tool to monitor the chirality of the binaphthyl compounds. [ABSTRACT FROM AUTHOR]

The composition of the lung tissue of mice was investigated using Raman confocal microscopy at 532 nm excitation wavelength and was supported with various staining techniques as well as DFT calculations. This combination of experimental and theoretical techniques allows for the study of the distribution of lung lipofibroblasts (LIFs), rich in vitamin A, as well as the chemical structure of vitamin A. The comparison of the Raman spectra derived from LIFs with the experimental and theoretical spectra of standard retinoids showed the ability of LIFs to store all-trans retinol, which is partially oxidized to all-trans retinal and retinoic acid. Moreover, we were able to visualize the distribution of other lung tissue components including the surfactant and selected enzymes (lipoxygenase/glucose oxidase). [ABSTRACT FROM AUTHOR]

The IR low-temperature Ar and Kr matrix spectra of l-isoserine were registered for the first time and interpreted by means of the anharmonic DFT frequencies calculated at the B3LYP/aug-cc-pVTZ and B3LYP/aug-cc-pVDZ levels. 54 l-isoserine conformers were predicted to be stable at the B3LYP/aug-cc-pVDZ level. Population of the 8 most stable conformers was based on the QCISD/aug-cc-pVDZ energies, corrected for thermal anharmonic factors obtained at the B3LYP/aug-cc-pVDZ level. We found several conformers to be present in the measured matrices and conformer 1to be dominating. Presence of the conformer 2is well confirmed by the ν(CO) band at 1790 cm−1and two bands at 1380 and 1350 cm−1. Presence of the conformer 4is quite well confirmed by the ν(C–O) bands at 1120 and 1095 cm−1. Slightly weaker arguments are found for the observation of conformers 6and 3. Calculations on 54 neutral and 5 zwitterionic conformers in water at the IEF-PCM/B3LYP/aug-cc-pVDZ level suggest that one neutral and one zwitterionic conformer co-exist in the aqueous environment. The crystal structure of l-isoserine was solved by X-ray diffraction analysis. The compound crystallizes without solvent in the chiral P21212 space group. The asymmetric unit contains a single molecule. The molecule is in its zwitterionic form with the CH2–NH3side chain in the gaucheconformation with respect to the hydroxyl group and in the anticonformation with respect to the carboxylate group. The structure of l-isoserine is dominated by a set of intermolecular hydrogen bonds. The strongest one appears between the OH and COOH groups of two neighbouring molecules: the OH contact is of 1.66(2) , which is amongst the shortest H-bonds of this kind observed in amino acid crystal structures. [ABSTRACT FROM AUTHOR]

Reports on highly efficient silver(I)-based thermally activated delayed fluorescence (TADF) materials are scarce due to challenges in molecular design, although these materials show great potential for photoluminescent and electroluminescent applications. Herein, a silver(I)-iodine cluster, namely Ag 2 I 2 (dppb-Ac) 2 , is synthesized by employing a donor-acceptor (D-A) type bisphosphine ligand. Due to the introduction of electron-donating iodine ligands, Ag 2 I 2 (dppb-Ac) 2 exhibits an emissive singlet state characterized by (metal + iodine)-to-ligand charge transfer and intra-ligand charge transfer transitions, as well as a small singlet-triplet energy gap. Additionally, its non-planar, highly distorted D-A structure efficiently separates adjacent molecules in aggregated state. As a result, Ag 2 I 2 (dppb-Ac) 2 exhibits efficient TADF and suppressed luminescence concentration quenching in thin films. For instance, the 10 wt%-doped PMMA film and neat film of Ag 2 I 2 (dppb-Ac) 2 display bright bluish-green and green emission, peaking at 506 and 532 nm, with photoluminescence quantum yields (PLQYs) of 70% and 52%, and lifetimes of 18.9 and 7.9 μs, respectively. The high PLQYs and efficiently suppressed emission concentration quenching of Ag 2 I 2 (dppb-Ac) 2 in films are outstanding among reported Ag(I)-based TADF emitters.

Catalytic alkene isomerization is a powerful synthetic strategy for preparing valuable internal alkenes from simple feedstocks. The utility of olefin isomerization hinges on the ability to control both positional and stereoisomerism to access a single product among numerous potential isomers. Within base-metal catalysis, relatively little is known about how to modulate reactivity and selectivity with group 6 metal-catalyzed isomerization. Here, we describe a tungsten-catalyzed, positionally selective alkene isomerization reaction in which tuning the ligand environment grants access to either the E - or Z -stereoisomer. The reactions employ simple, commercially available precatalysts and ligands. Preliminary mechanistic studies suggest that the ligand environment around 7-coordinate tungsten is crucial for stereoselectivity, and that substrate directivity prevents over-isomerization to the conjugated alkene. These features allow for exclusive formation of β,γ-unsaturated carbonyl compounds that are otherwise difficult to prepare., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Xanthone-based polyketides with complex molecular frameworks and potent bioactivities distribute and function in different biological kingdoms, yet their biosynthesis remains under-investigated. In particular, nothing is known regarding how to switch between the C 4a -C 10 (C 4a -selective) and C 10a -C 10 bond (C 10a -selective) cleavages of anthraquinone intermediates involved in biosynthesizing strikingly different frameworks of xanthones and their siblings. Enabled by our characterization of antiosteoporotic brunneoxanthones, a subfamily of polyketides from Aspergillus brunneoviolaceus FB-2, we present herein the brunneoxanthone biosynthetic gene cluster and the C 10a -selective cleavage of anthraquinone (chrysophanol) hydroquinone leading ultimately to the bioactive brunneoxanthones under the catalysis of BruN (an undescribed atypical non-heme iron dioxygenase) in collaboration with BruM as a new oxidoreductase that reduces the anthraquinone into its hydroquinone using NADPH as a cofactor. The insights into the driving force that determines whether the C 10a - or C 4a -selective cleavages of anthraquinone hydroquinones take place were achieved by a combination of multiprotein sequence alignment, directed protein evolution, theoretical simulation, chemical capture of hydroquinone tautomer, 18 O chasing, and X-ray crystal structure of the BruN N441M mutant, eventually allowing for the protocol establishment for the on-demand switch between the two ways of anthraquinone openings. Collectively, the work paves the way for the synthetic biology-based regeneration of uniquely structured high-value xanthones present in low abundance in complex mixtures, and helps to deepen the understanding on why and how such xanthones and their congeners are biosynthesized by different (micro)organisms in nature., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

We report the design, synthesis, electrochemical, UV-vis, fluorescence, and computational study of nine π-linked donor-acceptor (D-π-A) chromophores. The series of novel compounds comprises a terphenyl, terthiophene, or 2,5-diphenyl thiophene linker, with one electron-donating group (methyl or p-N , N -diethyl) and one electron-withdrawing group (nitrone, formyl, or dicyanovinyl) at opposite ends of the molecule. The HOMO-LUMO gaps were determined via cyclic voltammetry and found to correspond well to DFT-calculated values. Furthermore, the influence of the π-linker character and substituent on the HOMO-LUMO gap was analysed and interpreted in terms of MO composition via DFT., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A set of antimony(III) compounds containing a ligand (Ar) with a pendant guanidine function (where Ar = 2-[(Me 2 N) 2 CN]C 6 H 4 ) was prepared and characterized. This includes triorgano-Ar3Sb, diorgano-Ar2SbCl and monoorgano-ArSbCl2 compounds and they were characterized by 1 H and 13 C NMR spectroscopy and by single-crystal X-ray diffraction analysis (sc-XRD). The coordination capability of Ar3Sb and Ar2SbCl was examined in the reactions with either cis -[PdCl 2 (CH 3 CN) 2 ] or PtCl 2 and complexes cis -[(κ 2 -Sb,N-Ar3Sb)MCl 2 ] (M = Pd 1, Pt 2) and [(κ 3 -N,Sb,N-Ar2SbCl)MCl 2 ] (M = Pd 3, Pt 4) were isolated, while their structures were determined by sc-XRD. Notably, the ligands Ar3Sb and Ar2SbCl exhibit different coordination modes - bidentate and tridentate, respectively - and the antimony exhibits three distinct bonding modes in complexes 1-4, which were also subjected to theoretical studies.

Carbazole-based COFs were synthesized and applied as the sulfur-host in cathode materials for lithium-sulfur batteries (LSBs), which effectively mitigate the shuttle effect of lithium polysulfides. A high initial capacity of 1232 mAh g -1 at 0.1C is achieved, while also showing excellent capacity retention and stability in cyclic experiments. This work highlights the potential application of carbazole-based COFs for LSBs.

We report the synthesis of a heterobimetallic U(III)-Ir species which reacts with CS 2 to form the novel ethanetetrathiolate fragment via hydride insertion and C-C coupling. Computational studies suggest the formation of a radical intermediate, which may couple with another equivalent to form the final product.

Small-scale systems based on periodic boundary conditions often cannot accurately describe real-world situations, especially when conducting molecular dynamics simulations to study phase transitions, where it is very necessary to use large-scale systems. However, studying phase transitions in large-scale systems is an important and difficult task. Though ab initio molecular dynamics (AIMD), based on density functional theory (DFT), provides advantages in terms of accuracy, it is very difficult to study phase transitions in large-scale systems due to the considerable computational time required. In addition, although traditional empirical potentials are faster, their lower calculation accuracy makes it difficult to use them for phase transition studies. It is crucial to devise a method that has enabled a promising fusion of computational efficiency and precision to effectively investigate phase transitions in large-scale systems. In this work, the obtained machine learning potential function of carbon through deep neural networks not only demonstrates strong scalability but also effectively enables the study of the formation mechanisms of amorphous diamond and polycrystalline diamond using C 60 crystals and graphene as precursors under high-pressure high-temperature conditions (HPHT). Furthermore, the structure search software (AIRSS) was used to generate numerous initial structures which were optimized using the machine learning potential, a process which led to finding new structural clusters of carbon. Interestingly, the predictive capabilities of the machine learning potential for symmetric and asymmetric carbon clusters aligned well with the Gaussian approximation potential (GAP), yet the former demonstrated higher computational efficiency, making it more suitable for carbon material research. The results of this work signify significant progress in the field of carbon transition study, opening up new possibilities for exploring and understanding carbon materials with improved computational efficacy.

Inter-metalloid clusters in Zintl chemistry have been extensively studied due to their unique electronic structures and potential applications. In this work, we explored a series of actinide endohedral inter-metalloid clusters of the group 15 elements [An@Bi 12 ] 4- (An = Th-U) and [An@Sb 12 ] 4- using density functional theory (DFT). [Th@Bi 12 ] 4- and [U@Bi 12 ] 4- exhibit C s symmetry, while [Pa@Bi 12 ] 4- and [An@Sb 12 ] 4- (An = Th-U) have C 1 structures. Bonding analyses such as bond order, molecular orbitals (MO) and quantum theory of atoms in molecules (QTAIM) show covalent An-Bi/An-Sb bonding in the clusters. All these clusters are highly stable according to the studied formation reactions and may be accessible experimentally. Compared with [An@Bi 12 ] 4- , [An@Sb 12 ] 4- possesses stronger bonding interactions, mainly arising from the higher electrostatic interaction energy. For clusters with the same group 15 elements, the bonding interactions increase gradually from Th to U, which is mainly determined by the covalent interactions of An-Bi/An-Sb bonding. This work is expected to provide potential avenues for the construction of robust inter-metalloid clusters of the group 15 elements.

The installation of fluorine and fluorinated functional groups in organic molecules perturbs the physicochemical properties of those molecules and enables the development of new therapeutics, agrichemicals, biological probes and materials. However, current synthetic methodologies cannot access some fluorinated functional groups and fluorinated scaffolds. One such group, the gem -difluorobenzyl motif, might be convergently synthesized by reacting a nucleophilic aryl precursor and an electrophilic gem -difluoroalkene. Previous attempts have relied on forming unstable anionic or organometallic intermediates that rapidly decompose through a β-F elimination process to deliver monofluorovinyl products. In contrast, we report a fluorine-retentive palladium and copper co-catalyzed chloro-arylation of gem -difluorostyrenes that takes advantage of a nitrite (NO 2 - ) additive to avoid the favorable β-F elimination pathway that forms monofluorinated products, instead delivering difluorinated products., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Axially chiral C2-arylquinoline has been successfully constructed via asymmetric heteroannulation of alkynes catalyzed by chiral phosphoric acid with high yield and high enantioselectivity. Inspired by this intriguing work, theoretical calculations have been carried out, and the detailed reaction mechanism has been elaborated, in which the whole reaction can be divided into steps including hydrogen transfer, C-N bonding, annulation reaction and the final dehydration processes. The initial hydrogen-transfer reaction has two possible pathways, while the subsequent C-N bonding process has eight possible pathways. Then, after the annulation reaction and the final dehydration processes, the major product and byproduct were formed. QTAIM and IGMH analyses were used to illustrate the role of weak intermolecular interactions in the catalytic process, and the distortion/interaction and EDA analyses provided a deeper understanding of the origin of enantioselectivity. The calculated results are consistent with the experimental results. This work would provide valuable insights into asymmetric reactions catalyzed by chiral phosphoric acid.

A new Ru-catalyzed C-H activation/cyclization reaction for the synthesis of 3- C -glycosyl isocoumarins and 2-glycosyl-4 H -chromen-4-ones with carbonyl sulfoxonium ylide glycogen are reported. In this catalytic system, benzoic acid and its derivatives react with carbonyl sulfoxonium ylide glycogen to yield isocoumarin C -glycosides, while 2-hydroxybenzaldehyde substrates react to produce chromone C -glycosides. These reactions were characterized by mild reaction conditions, broad substrate scope, high functional-group compatibility, and high stereoselectivity to yield several high-value isocoumarins and chromone skeleton-containing C -glycosides. The methods were successfully implemented in the context of large-scale reactions and the late-stage modification of complex natural products.

A novel Ta/Os heterobimetallic complex, [Ta(CH 2 t Bu) 3 (μ-H) 3 OsCp*], 2, is prepared by protonolysis of Ta(CH t Bu)(CH 2 t Bu) 3 with Cp*OsH 5 . Treatment of 2 and its iridium analogue [Ta(CH 2 t Bu) 3 (μ-H) 2 IrCp*], 1, with CO 2 under mild conditions reveal the efficient cleavage of CO 2 , driven by the formation of a tantalum oxo species in conjunction with CO transfer to the osmium or iridium fragments, to form Cp*Ir(CO)H 2 and Cp*Os(CO)H 3 , respectively. This bimetallic reactivity diverges from more classical CO 2 insertion into metal-X (X = metal, hydride, alkyl) bonds.

The adaptive structure and excellent actuation of dielectric elastomer actuators (DEAs) make them promising candidates for soft robotics, haptic interfaces and artificial muscles. A wide variety of elastomers have been synthesised and investigated as dielectrics. Inorganic polymers such as polysiloxanes and polyphosphazenes have a low glass transition temperature. While polydimethylsiloxane (PDMS) has made its way into DEAs, the latter has received little attention in this field. Here, we present a dielectric elastomer based on polyphosphazene modified with 2,2,2,-trifluoroethoxy groups as the dielectric, which exhibits a dielectric permittivity two times higher than polydimethylsiloxanes (PDMS), excellent elasticity and a high dielectric breakdown field. These properties enable fast, reliable actuation and higher electrostatic forces than conventional PDMS. The actuators can withstand repeated actuation cycles and are suitable for long-term reliability applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We conducted a study on the trajectory-dependent threshold effects of proton stopping power in LiF nanosheets using time-dependent density functional theory non-adiabatically coupled to the molecular dynamics. This study covered protons with initial velocities in the range of 0.1-1.0 a.u., offering a vast amount of detailed information on the electronic structure during the stopping process with superior spatial and temporal resolution. Our results show that the impact parameters of incident protons play a crucial role in determining the threshold behavior of proton stopping power in LiF nanosheets. Most importantly, we found that close collisions do not exhibit a discernible threshold. In addition, the research results also revealed the time dependence of the number of electrons occupying the atomic orbitals of F and Li as protons pass through the nanosheets.

Using different prebiotically plausible activating reagents, the RNA ligation yield was significantly increased in the presence of Mn(II). The mechanism of the activation reaction has been investigated using 5'-AMP as an analogue.

In this study, a benzoselenadiazole- and pyridine-bifunctionalized hydrogen-bonded arylamide foldamer was synthesized. A co-crystallization experiment with 1,4-diiodotetrafluorobenzene showed that a new type of supramolecular double helices, which were induced by three orthogonal interactions, namely, three-center hydrogen bonding (O⋯H⋯O), I⋯N halogen bonding and Se⋯N chalcogen bonding, have been constructed in the solid state. This work presents a novel instance of multiple non-covalent interactions that work together to construct supramolecular architectures.

Transition metal multimetallic complexes have seen intense study due to their unique bonding and potential for cooperative reactivity, but actinide-transition metal (An-TM) species are far less understood. We have synthesized uranium- and thorium-osmium heterometallic polyhydride complexes in order to study An-Os bonding and investigate the reactivity of An-Os interactions. Computational studies suggest the presence of a significant bonding interaction between the actinide center and the four coordinated osmium centers supported by bridging hydrides. Upon photolysis, these complexes undergo intramolecular C-H activation with the formation of an Os-Os bond, while the thorium complex may activate an additional C-H bond of the benzene solvent, resulting in a μ-η 1 ,η 1 phenyl ligand across one Th-Os interaction., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Non-targeted analysis of high-resolution mass spectrometry (MS) can identify thousands of compounds, which also gives a huge challenge to their quantification. The aim of this study is to investigate the impact of mass spectrometry ionization efficiency on various compounds in food at different solvent ratios and to develop a predictive model for mass spectrometry ionization efficiency to enable non-targeted quantitative prediction of unknown compounds. This study covered 70 compounds in 14 different mobile phase ratio environments in positive ion mode to analyze the rules of the matrix effect. With the organic phase ratio from low to high, most compounds changed by 1.0 log units in log IE. The addition of formic acid enhanced the signal but also promoted the matrix effect, which often occurred in compounds with strong ionization capacity. It was speculated that the matrix effect was mainly in the form of competitive charge and charged droplet' gasification sites during MS detection. Subsequently, we present a log IE prediction method built using the COSMO-RS software and the artificial neural network (ANN) algorithm to address this difficulty and overcome the shortcomings of previous models, which always ignore the matrix effect. This model was developed following the principles of QSAR modeling recommended by the Organization for Economic Cooperation and Development (OECD). Furthermore, we validated this approach by predicting the log IE of 70 compounds, including those not involved in the log IE model development. The results presented demonstrate that the method we put forward has an excellent prediction accuracy for log IE ( R 2 pred = 0.880), which means that it has the potential to predict the log IE of new compounds without authentic standards.

Separation of lanthanide (Ln) and minor actinide (MA) elements and mutual separation between minor actinide elements ( e.g. Am(III) and Cm(III)) represent a crucial undertaking. However, separating these elements poses a significant challenge owing to their highly similar physicochemical properties. Asymmetric N-heterocyclic ligands such as N -ethyl-6-(1 H -pyrazol-3-yl)- N -( p -tolyl)picolinamide (Et- p -Tol-A-PzPy) and N -ethyl- N -( p -tolyl)-1,10-phenanthroline-2-carboxamide (ETPhenAm) have recently received considerable attention in the separation of MAs over Ln from acid solutions. By changing the central skeleton structures of these ligands and introducing substituents with different properties on the side chains, their complexation behavior with Am(III), Cm(III), and Eu(III) may be affected. In this work, we explore four different asymmetric N-containing heterocyclic ligands, namely Et- p -Tol-A-PzPy (L 1 ), N -ethyl-6'-(1 H -pyrazol-3-yl)- N -( p -tolyl)-[2,2'-bipyridine]-6-carboxamide (L 2 ), N -ethyl-9-(1 H -pyrazol-3-yl)- N -( p -tolyl)-1,10-phenanthroline-2-carboxamide (L 3 ), and ETPhenAm (L 4 ) using density functional theory (DFT). The calculated results demonstrate the potential of ligands L 1 -L 4 for the extraction and separation of Am(III), Cm(III), and Eu(III). Ligand analysis shows that ligand L 3 binds more easily to the central metal atom, in line with the stronger extraction capacity of L 3 . In spite of the higher covalence between the side chain and the central metal atom for complexes with L 1 -L 3 , the main chain seems to control the stability of the extraction complexes. The preorganized 1,10-phenanthroline backbone also further enhances the extraction performance of L 3 and L 4 . The difference in coordination ability between the side chain donors of these ligands and metal ions may affect their separation efficiency. This work presents theoretical insights into synthesizing novel ligands for separating trivalent actinides by adjusting N-heterocyclic ligands.

Metal nanoclusters (NCs) capable of near-infrared (NIR) photoluminescence (PL) are gaining increasing interest for their potential applications in bioimaging, cell labelling, and phototherapy. However, the limited quantum yield (QY) of NIR emission in metal NCs, especially those emitting beyond 800 nm, hinders their widespread applications. Herein, we present a bright NIR luminescence (PLQY up to 36.7%, ∼830 nm) bimetallic Cu 4 Pt 2 NC, [Cu 4 Pt 2 (MeO-C 6 H 5 -C[triple bond, length as m-dash]C) 4 (dppy) 4 ] 2+ (dppy = diphenyl-2-pyridylphosphine), with a high yield (up to 67%). Furthermore, by modifying the electronic effects of R in RC[triple bond, length as m-dash]C - (R = MeO-C 6 H 5 , F-C 6 H 5 , CF 3 -C 6 H 5 , Nap, and Biph), we can effectively modulate phosphorescence properties, including the PLQY, emission wavelength, and excited state decay lifetime. Experimental and computational studies both demonstrate that in addition to the electron effects of substituents, ligand modification enhances luminescence intensity by suppressing non-radiation transitions through intramolecular interactions. Simultaneously, it allows the adjustment of emitting wavelengths by tuning the energy gaps and first excited triplet states through intermolecular interactions of ligand substituents. This study provides a foundation for rational design of the atomic-structures of alloy metal NCs to enhance their PLQY and tailor the PL wavelength of NIR emission., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Herein, a facile strategy was established to build mechanoresponsive luminogens with high sensitivity to substituents and positional effects. Even in slightly different structures, distinct optical phenomena, including fluorescence efficiency and mechano-responsive properties, were clearly present. Outstanding mechanical-induced emission enhancement (5-100 times) properties and reversibility makes for promising applications in pressure sensors and OLEDs.

Ovonic threshold switching (OTS) selectors can effectively improve the storage density and suppress the leakage current of advanced phase-change memory devices. As a prototypical OTS material, amorphous GeSe is widely investigated. But the attention paid to amorphous Se ( i.e. , the functional constituent in amorphous GeSe) has been very limited up to now. Here we have explored the structure, bonding and electronic characteristics of amorphous Se using ab initio molecular dynamics simulations. The results reveal that the Se atoms in amorphous Se tend to form 2-coordinated configurations, and they connect with each other to form long chains. The fraction of the vibrational density of state located in the high frequency range is relatively large, and the formation energy of the Se-Se bond is as large as 4.44 eV, hinting that the Se-Se bonds in chains possess high stability. In addition, the mid-gap state related to the OTS behavior is also found in amorphous Se despite the small proportion. Our findings enrich the knowledge of amorphous Se, which aids the applications of Se-based OTS selectors.

We construct a single quantum dot-based nanosensor for piRNA detection based on ligation-mediated multi-cycle signal amplification. This nanosensor is homogenous, selective, and sensitive with a detection limit of 0.104 fM. Moreover, it can detect the endogenous piRNA level in different cell lines, and discriminate cancer tissues from normal tissues.

Boron-carbon compounds have been shown to have feasible superconductivity. In our earlier paper [Zheng et al. , Phys. Rev. B , 2023, 107 , 014508], we identified a new conventional superconductor of LiB 3 C at 100 GPa. Here, we aim to extend the investigation of possible superconductivity in this structural framework by replacing Li atoms with 27 different cations from periods 3, 4, and 5 under pressures ranging from 0 to 100 GPa. Using the high-throughput screening method of zone-center electron-phonon interaction, we found that ternary compounds like CaB 3 C, SrB 3 C, TiB 3 C, and VB 3 C are promising candidates for superconductivity. The consecutive calculations using the full Brillouin zone confirm that they have a T c of <31 K at moderate pressures. Our study demonstrates that fast screening of superconductivity by calculating zone-center electron-phonon coupling strength is an effective strategy for high-throughput identification of new superconductors.

In this paper, two types of solid phase 2D and 3D XBOFs were selectively constructed from identical building blocks of tetraphenylmethane tetrapyridine derivative and 1,4-diiodotetrafluorobenzene by changing the crystallization solvent. This 3D XBOF is a novel hybrid supramolecular organic framework with the synergistic control of hydrogen and halogen bonds.

Enzymes are versatile and efficient biological catalysts that drive numerous cellular processes, motivating the development of enzyme design approaches to tailor catalysts for diverse applications. In this perspective, we investigate the unique properties of natural, evolved, and designed enzymes, recognizing their strengths and shortcomings. We highlight the challenges and limitations of current enzyme design protocols, with a particular focus on their limited consideration of long-range electrostatic and dynamic effects. We then delve deeper into the impact of the protein environment on enzyme catalysis and explore the roles of preorganized electric fields, second coordination sphere interactions, and protein dynamics for enzyme function. Furthermore, we present several case studies illustrating successful enzyme-design efforts incorporating enzyme strategies mentioned above to achieve improved catalytic properties. Finally, we envision the future of enzyme design research, spotlighting the challenges yet to be overcome and the synergy of intrinsic electric fields, second coordination sphere interactions, and conformational dynamics to push the state-of-the-art boundaries., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A novel binuclear Cu(I) halide complex, Cu 2 I 2 (DPPCz) 2 , which emits efficient thermally activated delayed fluorescence (TADF), is reported. The crystal of this complex spontaneously undergoes ligand rotation and coordination-configuration transformation, converting to its isomer without any external stimulation.

The stopping power of energetic He ions traversing an Al film is studied by combining the time-dependent density-functional theory method with molecular dynamics simulations. We investigated the dependence of the semicore electron excitation of the Al film on the projectile's trajectory and its charge state. Our results show that for the off-channeling trajectories the semicore electrons contribute significantly to the stopping power of the Al film as the He + ion velocity exceeds 1.0 a.u, and in contrast, it is negligible for the channeling trajectories. Most importantly, we found two unexpected effects of semicore electrons on the stopping power in helium-irradiated aluminum nanosheets, i.e. , (1) the semicore electrons can contribute to the energy loss for both high and low energy projectiles under the off-channeling trajectory; (2) as the projectile velocity increases from 0.4 a.u. to 2.0 a.u. although semicore electron excitation (including transition in the target, ionization away from the target and transfer to the projectile ion) of the target atom is gradually inhibited, the influence of semicore electrons on valence electron excitation is gradually enhanced. Our finding allows us to gain new insights into the stopping of ions in metals.

The computational treatment of large molecular structures is of increasing interest in fields of modern chemistry. Accordingly, efficient quantum chemical approaches are needed to perform sophisticated investigations on such systems. This engaged the development of the well-established "Our own N-layered integrated molecular orbital and molecular mechanics" (ONIOM) multi-layer scheme [L. W. Chung et al. , Chem. Rev. , 2015, 115 , 5678-5796]. In this work, we present the specific implementation of the ONIOM scheme into the xtb semi-empirical extended tight-binding program package and its application to challenging transition-metal complexes. The efficient and broadly applicable GFN n -xTB and -FF methods are applied in the ONIOM framework to elucidate reaction energies, geometry optimizations, and explicit solvation effects for metal-organic systems with up to several hundreds of atoms. It is shown that an ONIOM-based combination of density functional theory, semi-empirical, and force-field methods can be used to drastically reduce the computational costs and thus enable the investigation of huge systems at almost no significant loss in accuracy.

This review summarizes the structures, biochemical properties, and mechanisms of two major biological sources of ethylene, the ethylene-forming enzyme (EFE) and 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACCO). EFE is found in selected bacteria and fungi where it catalyzes two reactions: (1) the oxygen-dependent conversion of 2-oxoglutarate (2OG) to ethylene plus three molecules of CO 2 /bicarbonate and (2) the oxidative decarboxylation of 2OG while transforming l-arginine to guanidine and l-Δ 1 -pyrroline-5-carboxylic acid. ACCO is present in plants where it makes the plant hormone by transforming ACC, O 2 , and an external reductant to ethylene, HCN, CO 2 , and water. Despite catalyzing distinct chemical reactions, EFE and ACCO are related in sequence and structure, and both enzymes require Fe(ii) for their activity. Advances in our understanding of EFE, derived from both experimental and computational approaches, have clarified how this enzyme catalyzes its dual reactions. Drawing on the published mechanistic studies of ACCO and noting the parallels between this enzyme and EFE, we propose a novel reaction mechanism for ACCO., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)