Notes

Transcriptome along with phytochemical analyses offer experience into the organic and natural sulfur pathway throughout Allium hirtifolium.
Correction for 'Influence of residual water and cation acidity on the ionic transport mechanism in proton-conducting ionic liquids' by Jingjing Lin et al., Phys. Chem. Chem. Phys., 2020, 22, 1145-1153.Based on first-principles calculations, multiferroic properties of orthorhombic manganites (RMnO3, R = La-Lu) with E-type ground state have been achieved by lanthanide contraction (chemical pressure) and/or external strain. Our research demonstrates that a smaller R radius within the octahedral voids in RMnO3 results in the increase in the tilts of the octahedra but only a gentle change in the Jahn-Teller (JT) distortion. The reduction of the intraplane octahedral rotation angle and the narrowed eg states and lifting t2g band edge are mainly responsible for the intraplane magnetic transition from ferromagnetic (La-Gd) to zigzag-like spin arrangement (Ho-Lu). In turn, the center-broken E-type RMnO3 bulk characterizes the dominated electronic polarization behavior, benefiting from their distortion response to small R substitution, which gives rise to the strong magnetoelectricity. Subsequently, we have figured out the strain strategy for obtaining an E-type transition in light rare-earth manganites (La-Gd) by imposing a series of hypothetical strains, where the small intraplane rotation angle (Θ) and large JT distortion favor the small aspect ratios of a/b and c/b, respectively. The strained LaMnO3 and GdMnO3 achieve E-type transitions successfully by imposing a modest compressive strain along the a- and c-axes and remaining free along the b-direction. Simultaneously, their polarization behaviors were comparatively studied. It was found that the size of the A-site rare-earth ions has a great influence on the external strain response, in addition to its effect on the magnetic phase transition.The role of frustrated Lewis pairs (FLPs) as ligands in gold(i) catalyzed-reactions has been computationally investigated by using state-of-the-art density functional theory calculations. To this end, the nature of (P,B)-FLP-transition metal interactions in different gold(i)-complexes has been first explored in detail with the help of the energy decomposition analysis method, which allowed us to accurately quantify the so far poorly understood AuB interactions present in these species. The impact of such interactions on the catalytic activity of gold(i)-complexes has been then evaluated by performing the Au(i)-catalyzed hydroarylation reaction of phenylacetylene with mesitylene. With the help of the activation strain model of reactivity, the factors governing the higher activity of Au(i)-complexes having a FLP as a ligand as compared to that of the parent PPh3 system have also been quantitatively identified.A novel class of transmembrane anion carriers, the click-tambjamines, display remarkable anionophoric activities in model liposomes and living cells. The versatility of this building block for the generation of molecular diversity offers promise to develop future drugs based on this design.Low cost Cu-based catalysts are attractive options in catalyzing higher alcohol synthesis (HAS) from syngas. Introducing isolated Rh single atoms into the surfaces of these Cu catalysts has the potential to dramatically improve the performance of these Cu-based catalysts. In this work, extensive density functional theory (DFT) calculations were performed with periodic slab models to systematically investigate the possibility of using Rh/Cu single-atom alloys (SAAs) as HAS catalysts. The mechanism of ethanol synthesis from syngas on the representative Rh/Cu(111) and Rh/Cu(100) surfaces was elucidated. All possible formation pathways of the C1 and C2 fragments leading to the ethanol main product, as well as the methane and methanol by-products were considered. Our calculations show that for ethanol formation, the C-C bond coupling is easier over the Rh/Cu SAA catalysts than pure Cu catalysts, suggesting that Rh/Cu SAA catalysts are more favorable for the formation of higher alcohols.Molecular sieves are of increasing importance in catalysis, the oil industry, and biomedicine. Traditional molecular sieves are generally oxides that inevitably show some absorption in the mid- and far-IR range due to the vibrations of metal-oxygen bonds, which are unfavorable for the in situ observation of the reactions in molecular sieves through IR techniques. In this study, a new metal halide In[Ba3Cl3F6] has been synthesized. It exhibits a quite transparent window from 0.366 to 22 μm and good adsorption and desorption processes.A major challenge in the field of photocatalytic carbon dioxide (CO2) reduction is to design catalyst systems featuring high selectivity for CO production, long-term stability and a composition of Earth-abundant elements. Here, we present a metal-organic framework (MOF) based catalyst to mitigate the technical problems associated with the above-mentioned features. We report a carbon-coated CuNi alloy nanocatalyst obtained by high temperature vacuum treatment of a MOF material (CuNiBTC). The resulting carbon encapsulated CuNi (denoted as CuNi/C) nanoparticles possess a well-designed core-shell composite structure with graphene shells. Meanwhile, we investigated the reaction mechanism of CO2 on the surface of the CuNi/C photocatalyst in an aqueous solution containing triethanolamine. The experimental results show that the activity and catalytic yield of CuNi/C are much higher than those of Cu/C and Ni/C alone. At the same time, the catalytic activity of CuNi/C is also affected by changing the reaction temperature in the preparation process. As a result, the CuNi/C samples can achieve nearly 90% selectivity for NIR-light-driven CO2 reduction to CO. Our approach demonstrates the potential of non-semiconductor materials as catalysts for efficient and selective reduction of CO2 to CO.Biredox ionic liquids are a new class of functionalized electrolytes that may play an important role in future capacitive energy storage devices. By allowing additional storage of electrons inside the liquids, they can improve device performance significantly. However current devices employ nanoporous carbons in which the diffusion of the liquid and the adsorption of the ions could be affected by the occurrence of electron-transfer reactions. It is therefore necessary to understand better the thermodynamics and the kinetics of such reactions in biredox ionic liquids. Here we perform ab initio molecular dynamics simulations of both the oxidized and reduced species of several redox-active ionic molecules (used in biredox ionic liquids) dissolved in acetonitrile solvent and compare them with the bare redox molecules. We show that in all the cases, it is necessary to introduce a two Gaussian state model to calculate the reaction free energies accurately. These reaction free energies are only slightly affected by the presence of the IL group on the molecule. We characterize the structure of the solvation shell around the redox active part of the molecules and show that in the case of TEMPO-based molecules strong reorientation effects occur during the oxidation reaction.Acceptor-donor-acceptor triads consisting of diketopyrrolopyrrole (DPP) or pyrrolopyrrole aza-BODIPY (PPAB) or both as acceptors and cyclopentadithiophene as a donor were rationally designed for near infrared (NIR) photovoltaics application. Among them, the PPAB-based triad exhibited the highest power conversion efficiency of 3.88% owing to the panchromatic absorption in the UV/vis/NIR regions.A copper-catalyzed three-component reaction of O-acyl oximes, DABCO·(SO2)2, and 2H-azirines under mild conditions has been achieved. This protocol provides an efficient route for the construction of various tetrasubstituted β-sulfonyl N-unprotected enamines in moderate to good yields with excellent stereoselectivity and regioselectivity. Notably, this method represents a rare example of 2H-azirines as useful synthons for β-functionalized N-unprotected enamines. Preliminary mechanistic studies indicate that the reaction proceeds through coupling of a sulfonyl radical and α-carbon radical via copper-catalyzed ring-opening C-C bond cleavage of O-acyl oxime and C-N bond cleavage of 2H-azirine with the insertion of sulfur dioxide.Density Functional Theory (DFT) calculations of electrode material properties in high energy density storage devices like lithium batteries have been standard practice for decades. In contrast, DFT modelling of explicit interfaces in batteries arguably lacks universally adopted methodology and needs further conceptual development. In this paper, we focus on solid-solid interfaces, which are ubiquitous not just in all-solid state batteries; liquid-electrolyte-based batteries often rely on thin, solid passivating films on electrode surfaces to function. We use metal anode calculations to illustrate that explicit interface models are critical for elucidating contact potentials, electric fields at interfaces, and kinetic stability with respect to parasitic reactions. The examples emphasize three key challenges (1) the "dirty" nature of most battery electrode surfaces; (2) voltage calibration and control; and (3) the fact that interfacial structures are governed by kinetics, not thermodynamics. To meet these challenges, developing new computational techniques and importing insights from other electrochemical disciplines will be beneficial.LiNi0.8Co0.1Mn0.1O2 is one of the most promising cathode materials for lithium ion batteries; however, during the charge/discharge process, it suffers from capacity fading, which is considered to be due to intergranular cracking. Herein we develop an original concept to alleviate this problem via negative pressure immersion treatment. A 3D-SiO2 framework is formed in the intergranular voids and at grain boundaries (functioning as the buffer zone and transfer-bridge) and the SiO2 protective layer is completely and homogeneously coated on the surfaces of the pristine particles through a hydrolytic condensation reaction involving tetraethoxysilane (TEOS). The 3D-SiO2 framework has two advantages firstly, acting as a buffer zone, the framework can effectively inhibit the generation and extension of intergranular cracking; secondly, like the SiO2 protective layer on the surface of the particles, the 3D-SiO2 framework can impede side reactions between primary particles (grains) and electrolyte inside the particles. As a result, the as-modified LiNi0.8Co0.1Mn0.1O2 exhibits enhanced cycling performance with 92.4% capacity retention after 100 cycles at 1 C (200 mA h·g-1), while the capacity retention values for the pristine particles and normal coating treatment particles are only 55.4% and 82.6%, respectively. Moreover, the thermal stability (60 °C) is distinctly enhanced and the rate performance is significantly improved at high rates (2, 3 and 5 C).Nickel complexes with non-innocent ligands generated by one-electron reduction of octahedral Schiff base nickel(ii) complexes with hemilabile ligands exhibited excellent catalytic activities of over 5000 TONs through a metal-ligand cooperation mechanism for hydrogen evolution from water under visible light irradiation.A variety of quaternary aryl amino acid derivatives can be synthesised using tandem SN2/Smiles rearrangement chemistry involving aryl sulfonamides and α-chloro carbonyl compounds. The reaction harnesses a sulfur dioxide extrusion pathway to construct a C-N and C-Caryl bond under simple conditions with no requirement for organometallics or transition metal catalysts. The reaction is also successful for alkenyl sulfonamides, producing sterically congested quaternary alkene amino acid derivatives.
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