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The integration of solid oxide cells (SOCs) into circular economy is crucial to enable efficient preservation of critical and high-cost resources such as rare earth elements, cobalt, and nickel used in conventional SOC applications. Based on the fuel electrode-supported cell (FESC) design, a semi-closed loop recycling approach was applied for cell material from CeramTec/Forschungszentrum Jülich. We show that more than 85 wt% of the ceramic components can be successfully reprocessed to new fuel electrode-based substrate that can be further used in cell production. Reprocessing of sintered bodies requires a multi-stage procedure. Increasing the amount of recyclate in the substrate leads to changes in substrate properties such as higher porosities and reduced shrinkage.

18th International Symposium on Solid Oxide Fuel Cells (SOFC-XVIII), Boston, USA, USA, 28 May 2023 - 2 Jun 2023; ECS transactions 111(6), 1657 - 1665 (2023). doi:10.1149/11106.1657ecst, Published by Pennington, NJ

Journal of the American Chemical Society 145(20), 11440 - 11448 (2023). doi:10.1021/jacs.3c03270, Silafulleranes with endohedral Cl$^−$ ions are a unique,scarcely explored class of structurally well-defined silicon clustersand host-guest complexes. Herein, we report regioselectivederivatization reactions on the siladodecahedrane [nBu$_4$N][Cl@Si$_{20}$(SiCl$_3$)$_{12}$Cl$_8$] ([nBu$_4$N][1]), which has its cluster surfacedecorated with 12 SiCl$_3$ and 8 Cl substituents in perfect T$_h$ symmetry. The room-temperature reaction of [nBu$_4$N][1] withexcess iBu$_2$AlH in ortho-difluorobenzene (oDFB) furnishesperhydrogenated [nBu$_4$N][Cl@Si$_{20}$(SiH$_3$)$_{12}$H$_8$] ([nBu$_4$N][2]) in 50% yield; the non-pyrophoric [2]$^−$ is the largest structurallyauthenticated (by X-ray diffraction) hydridosilane known to date. Asimple switch from pure oDFB to an oDFB/Et$_2$O solvent mixturesuppresses core hydrogenation and results in the formation of[nBu$_4$N][Cl@Si$_{20}$(SiH$_3$)$_{12}$Cl$_8$] ([nBu$_4$N][3]). In addition to the exhaustive Cl/H exchange at all 44 Si−Cl bonds of [1]$^−$ and theregioselective 36-fold silyl group hydrogenation, we achieved the simultaneous introduction of Me substituents at all 8 SiCl verticesalong with the conversion of all 12 SiCl$_3$ to SiH$_3$ groups by treating [nBu$_4$N][1] with Me$_2$AlH/Me$_3$Al in oDFB ([nBu$_4$N][Cl@Si$_{20}$(SiH$_3$)$_{12}$Me$_8$], [nBu$_4$N][4]; 73%). Quantum-chemical free-energy calculations find an SN$_2$-Si-type hydrogenation of theexohedral SiCl$_3$ moieties in [1]$^−$ (trigonal-bipyramidal intermediate) slightly preferred over metathesis-like SNi-Si substitutions (four-membered transition state). Cage hydrogenation likely occurs via SNi-Si processes. The experimentally demonstrated influenceof an Et$_2$O co-solvent, which drastically increases the respective reaction barriers, is attributed to the increased stability of theresulting iBu$_2$AlH-OEt$_2$ adduct and its higher steric bulk compared to free iBu$_2$AlH., Published by ACS Publications, Washington, DC

Antioxidants & redox signaling : ARS 10, ars.2022.0090 (2022). doi:10.1089/ars.2022.0090, Published by Liebert, Larchmont, NY

Single-atoms on carbon–nitrogen supports are considered catalysts for a multitude of reactions. However, doubts remain whether really these species or subnanometer clusters formed under reaction conditions are the active species. In this work, we investigate the dynamics of palladium single-atoms on graphitic carbon nitride during ethylene hydrogenation and H2-D2 exchange. By employing aberration-corrected scanning transmission electron microscopy, x-ray photoelectron spectroscopy and x-ray absorption spectroscopy, we will show that palladium, originally present as single-atoms, agglomerates to clusters at 100 °C in a gas atmosphere that contains both ethylene and hydrogen. This agglomeration goes in hand with the emergence of catalytic activity in both ethylene hydrogenation and H2-D2 exchange, suggesting that clusters, rather than single-atoms, are the active species. The results presented herein highlight the potential of analytics over the course of reaction to identify the active species and provide new insights into the influence of gas atmosphere on metal speciation.

A thermoresponsive and recyclable nanomaterial was synthesized by surface modification of magnetite nanoparticles (MNPs) with poly(N-isopropylacrylamide-co-diethylaminoethyl methacrylate) (P(NIPAAm-co-DEAEMA)), having PNIPAAm as a thermoresponsive moiety and PDEAEMA for catalyst binding. Palladium (Pd) nanoparticles were incorporated into this material, and the resulting nanocatalyst was efficient in the hydrogenation of olefins and nitro compounds with turnover frequencies (TOFs) up to 750 h–1. Consistent catalytic activity in 10 consecutive runs was observed when performing the hydrogenation at 45 °C, i.e., above the lower critical solution temperature (LCST) of the copolymer (37 °C), followed by cooling to 15 °C, i.e., below the LCST of the copolymer.

10.1021/acsmacrolett.3c00019

Metallic lithium reacts with organic solvents, resulting in their decomposition. The prevention of these decomposition reactions is a key aspect enabling the use of metallic lithium as an anode in lithium metal batteries. Scanning electrochemical microscopy (SECM), laser microscopy, and Fourier transform infrared (FT-IR) spectroscopy were used to analyze the effect of a graphite coating on metallic lithium. The graphite layer successfully prevents the agglomeration of decomposition products on the surface. SECM data show that the surface of untreated lithium metal in electrolyte is insulating, but the surface of the graphite coated lithium appears conducting and is therefore not covered by any layer of decomposition products. The protective properties of the graphite layer were proofed using FT-IR data. No significant differences in the spectra evolved during immersion of the sample in the electrolyte. Electrochemical plating experiments and post-mortem analysis revealed that the graphite layer did not result in homogeneous lithium plating depending on the current density. At high currents, no fully covering layer of decomposition products was formed on the surface during plating experiments, indicating a more complex mechanism of solid–electrolyte interface formation.

The unknown human gut bacterium mannoside phosphorylase (UhgbMP) is involved in the metabolization of eukaryotic N-glycans lining the intestinal epithelium, a factor associated with the onset and symptoms of inflammatory bowel diseases. In contrast with most glycoside phosphorylases, the putative catalytic acid of UhgbMP, Asp104, is far from the scissile glycosidic bond, challenging the classical Koshland mechanism. Using quantum mechanics/molecular mechanics metadynamics, we demonstrate that the enzyme operates by substrate-assisted catalysis via the 3-hydroxyl group of the mannosyl unit, following a 1S5/B2,5 → [B2,5]‡ → 0S2 conformational itinerary. Given the conservation of the active site hydrogen bond network across the family, this mechanism is expected to apply to other GH130 enzymes, as well as recently characterized mannoside phosphorylases with similar folds. Gaining insight into the catalytic reaction of these enzymes can aid the design of specific inhibitors to control interactions between gut microbes and the host.

Tuning the core–shell morphology of bimagnetic nanoparticles and its associated exchange bias behavior is a promising way to overcome the superparamagnetic limit and stabilize the particle moment in extended time and temperature ranges. The intraparticle magnetization distribution and magnetic coupling between the two phases, however, is still unclear. We report a significant nonzero magnetization in the CoxFe(1–x)O core of native core–shell bimagnetic nanoparticles that is typically considered antiferro- or paramagnetic. Co0.14Fe0.86O@Co0.4Fe2.4O4 (6 nm@2 nm) and Co0.08Fe0.92O@Co0.58Fe2.28O4 (12 nm@2 nm) core–shell nanoparticles have been synthesized by thermal decomposition of a mixed cobalt–iron oleate with a similar Fe/Co distribution throughout the nanoparticle. We determine the exact phase composition and the magnetization distribution in the core and shell using a combination of X-ray and neutron small-angle scattering. Core and shell magnetization are traced separately with a varying magnetic field. Our results reveal that the magnetization of the core and the spinel-type shell phases are coupled at room temperature, i.e., rotating coherently with the magnetic field. This is a mandatory condition to observe a significant exchange bias effect at low temperatures. These findings highlight the enormous potential of finite size and exchange coupling in bimagnetic nanoparticles to control the magnetic properties via interface-induced magnetization.

Nature chemistry 15(5), 641 - 646 (2023). doi:10.1038/s41557-023-01148-7, The recent high-pressure synthesis of pentazolates and the subsequent stabilization of the aromatic $[N_5]^−$ anion at atmospheric pressure have had an immense impact on nitrogen chemistry. Other aromatic nitrogen species have also been actively sought, including the hexaazabenzene $N_6 $ring. Although a variety of configurations and geometries have been proposed based on ab initio calculations, one that stands out as a likely candidate is the aromatic hexazine anion $[N_6]^{4−}$. Here we present the synthesis of this species, realized in the high-pressure potassium nitrogen compound $K_9N_{56}$ formed at high pressures (46 and 61 GPa) and high temperature (estimated to be above 2,000 K) by direct reaction between nitrogen and $KN_3$ in a laser-heated diamond anvil cell. The complex structure of $K_9N_{56}$—composed of 520 atoms per unit cell—was solved based on synchrotron single-crystal X-ray diffraction and corroborated by density functional theory calculations. The observed hexazine anion $[N_6]^{4−}$ is planar and proposed to be aromatic., Published by Nature Publishing Group, London

Four divinylphenylene-bridged diruthenium complexes [{Ru(CO)(P i Pr3)2(L-κ 2 [N,O] – )}2(μ-CH=CH-C6H4-CH=CH-1,4)] (2a–2d) with N,O-chelating 2-hydroxypyridine and 2-hydroxy- or 8-hydroxyquinoline ligands are presented. They were studied by NMR spectroscopy, electrochemical methods and, in their neutral and oxidized states, by IR, UV/Vis/NIR and, if applicable, by EPR spectroscopy. The experimental studies are complimented by (TD-)DFT calculations. Our results indicate that the pyridine-olate complexes 2a,b exist as three isomers with a ratio of about 78:20:2 that differ with respect to the orientation of the N and O donors relative to the CO and alkenyl ligands in the equatorial coordination plane. Only the isomer with both imine N donors trans to the alkenyl ligand is observed for complexes 2c,d with quinolinato ligands. All complexes undergo two consecutive, chemically and electrochemically reversible one-electron oxidations at low potentials. Our results indicate strong contributions of the divinylphenylene bridge to the redox processes and an even delocalization of the electron hole and the unpaired spin density over the entire π-conjugated divinylphenylene diruthenium backbone with only minor involvement of the peripherally attached κ 2 [N,O] – donor ligands.

Varying the solution pH not only changes the reactant concentrations in bulk solution but also the local reaction environment (LRE) that is shaped furthermore by macroscopic mass transport and microscopic electric double layer (EDL) effects. Understanding ubiquitous pH effects in electrocatalysis requires disentangling these interwoven factors, which is a difficult, if not impossible, task without physical modeling. Herein, we demonstrate how a hierarchical model that integrates microkinetics, double-layer charging, and macroscopic mass transport can help understand pH effects of the formic acid oxidation reaction (FAOR). In terms of the relation between the peak activity and the solution pH, intrinsic pH effects without consideration of changes in the LRE would lead to a bell-shaped curve with a peak at pH = 6. Adding only macroscopic mass transport, we can already reproduce qualitatively the experimentally observed trapezoidal shape with a plateau between pH 5 and 10 in perchlorate and sulfate solutions. A quantitative agreement with experimental data requires consideration of EDL effects beyond Frumkin correlations. Specifically, the peculiar nonmonotonic surface charging relation affects the free energies of adsorbed intermediates. We further discuss pH effects of FAOR in phosphate and chloride-containing solutions, for which anion adsorption becomes important. This study underpins the importance of a full consideration of multiple interrelated factors for the interpretation of pH effects in electrocatalysis.

The zwitterionic halido cyclopentadienone iron complexes FeX(CO)2-NMe3 (X = Cl, Br, I) were prepared and characterized by NMR, XRD, MS, IR, and elemental analysis. Their catalytic performance in hydrogenation and transfer hydrogenation was assessed. Transfer hydrogenation in boiling iPrOH with acetophenone as the test substrate showed no conversion with FeI(CO)2-NMe3. Hydrogenation reactions under H2 pressure (7.5 bar) in water as solvent showed up to 93% conversion with FeI(CO)2-NMe3 (2.5 mol %) using acetophenone as the test substrate. The overall relative reactivity order was established to be Cl < Br < I, reflecting the relative bond strengths of the Fe–X bonds. Although the compounds presented in this study can be used as precatalysts for hydrogenation reactions in water, the need to employ high temperatures, leading to more catalyst decomposition, as evidenced by pressurized sample infusion-electrospray ionization–mass spectrometry (PSI-ESI-MS), and high catalyst loading limits their usefulness as catalysts. The limit can be circumvented in part by salt effects analogous to those in classical solvolysis chemistry., Inorganic Chemistry, 62 (10), ISSN:0020-1669, ISSN:1520-510X

Journal of chemical information and modeling 63(5), 1406-1412 (2023). doi:10.1021/acs.jcim.2c01620, Published by American Chemical Society, Washington, DC

Alkene carbonylation, in which hydrogenation plays pivotal roles, is one of the most efficient method for the production of oxygenated chemicals like aldehydes, amides, and esters, among others. In this work, using in situ produced hydrogen via a water–gas shift (WGS) reaction, selective ethylene carbonylation to 3-pentanone was achieved instead of hydroformylation to propionaldehyde with gaseous H2 on a defective ceria-supported Rh catalyst. The interface of Rh/CeO2, which consists of oxygen vacancies and positively charged Rh, activates water, CO, and ethylene and the subsequent reactions, including the WGS reaction and ethylene carbonylation. The lean hydrogen circumstance created by the WGS reaction suppresses the hydrogenation of the propionyl group and promotes its ethylation to 3-pentanone. A redox pathway was proposed for the WGS reaction based on the in situ FTIR results, and the origin of hydrogen for ethylene carbonylation is water, as confirmed by a mass spectrometry (MS) study using d2-water as one of the reactants. This work provides a promising method for heavier ketone synthesis.

Laser-induced magnetic dipole (LaserIMD) spectroscopy and light-induced double electron–electron resonance (LiDEER) spectroscopy are important techniques in the emerging field of light-induced pulsed dipolar electron paramagnetic resonance (EPR) spectroscopy (light-induced PDS). These techniques use the photoexcitation of a chromophore to the triplet state and measure its dipolar coupling to a neighboring electron spin, which allows the determination of distance restraints. To date, LaserIMD and LiDEER have been analyzed with software tools that were developed for a pair of two S=1/2 spins and that neglected the zero-field splitting (ZFS) of the excited triplet. Here, we explore the limits of this assumption and show that the ZFS can have a significant effect on the shape of the dipolar trace. For a detailed understanding of the effect of the ZFS, a theoretical description for LaserIMD and LiDEER is derived, taking into account the non-secular terms of the ZFS. Simulations based on this model show that the effect of the ZFS is not that pronounced in LiDEER for experimentally relevant conditions. However, the ZFS leads to an additional decay in the dipolar trace in LaserIMD. This decay is not that pronounced in Q-band but can be quite noticeable for lower magnetic field strengths in X-band. Experimentally recorded LiDEER and LaserIMD data confirm these findings. It is shown that ignoring the ZFS in the data analysis of LaserIMD traces can lead to errors in the obtained modulation depths and background decays. In X-band, it is additionally possible that the obtained distance distribution is plagued by long distance artifacts.

Journal of applied crystallography 56(1), 103 - 109 (2023). doi:10.1107/S1600576722010858, Finite size effects in partial pair distribution functions generate artefacts in the scattering structure factor and scattering intensity. It is shown how they can be overcome using a binned version of the Debye scattering equation. Accordingly, reverse Monte Carlo simulations are used for very small nanoparticles of LaFeO3 with diameters below 10 nm to simultaneously analyse X-ray scattering data and extended X-ray absorption fine structure spectra at the La K and Fe K edges. The structural information obtained is consistent regarding local structure and long-range order., Published by Wiley-Blackwell, [Erscheinungsort nicht ermittelbar]

Journal of magnesium and alloys (2022). doi:10.1016/j.jma.2022.12.004, Published by Elsevier, Amsterdam [u.a.]

Human activity has an ever-increasing impact on the environment. In order to understand all processes and interactions behind this change, one has to analyze the environmental impact. Life Cycle Assessments (LCAs) are one way to achieve this, which, however, are time-consuming and often associated with high costs, as well as the requirement of specialized knowledge and software. This paper introduces a model, which allows an initial assessment. The model enables a more pragmatic way and may be considered as a first step in order to implement ecological sustainability considerations into companies. Based on a real-world problem, namely the disposal of foundry dust, the model is explained in a vivid manner.

Journal of catalysis 418, 13-21 (2023). doi:10.1016/j.jcat.2022.12.029, Published by Elsevier, Amsterdam [u.a.]

Solvent extraction and ion exchange (2023). doi:10.1080/07366299.2023.2165405, Published by Taylor & Francis, Philadelphia, PA

The scientific objective of this study was to answer the question of whether sink limitation is also true for high quality wheat varieties. We examined the incorporation of 15N and 13C during phenological phases into vegetative parts and grains of Elite wheat Triso (E) and Quality wheat Naxos (A) when the spike is halved. Three splits of fertilizer were applied at EC 11, EC 30, EC 59, whereby 10% at EC 30 and EC 59 was 15N, and plants were also labelled with 13CO2. The application of only the third split as 15N, combined with spike-halving, resulted in a significantly higher 15N-content (+11%) of 0.486 mg 15N/g DM, compared to the control (0.437 mg15N/g DM). Labelling whole plants with 13CO2 at EC 59 resulted in a significantly higher 13C-content—40%—(0.223 mg 13C/g DM) of the grains of the control for Triso at the fully-ripe stage (EC 89), compared to Naxos (0.160 mg 13C/g DM). This superiority was reduced to 34%, and was also demonstrated by spike-halving (0.226 mg 13C/g DM, 0.169 mg 13C/g DM). Remobilization of 15N for control and spike-halving treatments were 68.2% and 61.1%, respectively. This clearly demonstrates that the reduction of the sink size by spike-halving leads to a 7% reduction in the remobilization of 15N from vegetative to reproductive tissues.

Human NEET proteins contain two [2Fe–2S] iron–sulfur clusters, bound to three Cys residues and one His residue. They exist in two redox states. Recently, these proteins have revealed themselves as attractive drug targets for mitochondrial dysfunction-related diseases, such as type 2 diabetes, Wolfram syndrome 2, and cancers. Unfortunately, the lack of information and mechanistic understanding of ligands binding to the whole functional, cytoplasmatic domain has limited rational drug design approaches. Here, we use an enhanced sampling technique, volume-based metadynamics, recently developed by a team involving some of us, to predict the poses and affinity of the 2-benzamido-4-(1,2,3,4-tetrahydronaphthalen-2-yl)-thiophene-3-carboxylate ligand to the entire surface of the cytoplasmatic domain of the human NEET protein mitoNEET (mNT) in an aqueous solution. The calculations, based on the recently published X-ray structure of the complex, are consistent with the measured affinity. The calculated free energy landscape revealed that the ligand can bind in multiple sites and with poses other than the one found in the X-ray. This difference is likely to be caused by crystal packing effects that allow the ligand to interact with multiple adjacent NEET protein copies. Such extra contacts are of course absent in the solution; therefore, the X-ray pose is only transient in our calculations, where the binding free energy correlates with the number of contacts. We further evaluated how the reduction and protonation of the Fe-bound histidine, as well as temperature, can affect ligand binding. Both such modifications introduce the possibility for the ligand to bind in an area of the protein other than the one observed in the X-ray, with no or little impact on affinity. Overall, our study can provide insights on the molecular recognition mechanisms of ligand binding to mNT in different oxidative conditions, possibly helping rational drug design of NEET ligands.

Glycans are involved in numerous biological recognition events. Being secondary gene products, their labeling by genetic methods – comparable to GFP labeling of proteins – is not possible. To overcome this limitation, metabolic glycoengineering (MGE, also known as metabolic oligosaccharide engineering, MOE) has been developed. In this approach, cells or organisms are treated with synthetic carbohydrate derivatives that are modified with a chemical reporter group. In the cytosol, the compounds are metabolized and incorporated into newly synthesized glycoconjugates. Subsequently, the reporter groups can be further derivatized in a bioorthogonal ligation reaction. In this way, glycans can be visualized or isolated. Furthermore, diverse targeting strategies have been developed to direct drugs, nanoparticles, or whole cells to a desired location. This review summarizes research in the field of MGE carried out in recent years. After an introduction to the bioorthogonal ligation reactions that have been used in in connection with MGE, an overview on carbohydrate derivatives for MGE is given. The last part of the review focuses on the many applications of MGE starting from mammalian cells to experiments with animals and other organisms. published

Depicting how biomolecules move and interact within their physiological environment is one of the hottest topics of structural biology. This Feature Article gives an overview of the most recent advances in Site-directed Spin Labeling coupled to Electron Paramagnetic Resonance spectroscopy (SDSL–EPR) to study biomolecules in living cells. The high sensitivity, the virtual absence of background, and the versatility of spin-labeling strategies make this approach one of the most promising techniques for the study of biomolecules in physiologically relevant environments. After presenting the milestones achieved in this field, we present a summary of the future goals and ambitions of this community. published

Chemical science 14(2), 284-290 (2023). doi:10.1039/D2SC05409D, We report a new method for the synthesis of nitrogen-doped (N-doped) polycyclic aromatic hydrocarbons (PAHs) by a Suzuki coupling/intramolecular S$_N$Ar cascade reaction. A one- or two-fold [3 + 3] naphtho-annulation of halogenated aniline was conducted under Suzuki–Miyaura cross-coupling conditions to yield a series of fully fused N-doped PAHs. In contrast to reported methods to synthesize pyridinic or pyrrolic nitrogen-doped PAHs, our method enables preparation of PAHs doped with graphitic nitrogen, for which few reports are known in the literature. The crystal structure as well as absorption, fluorescence and electrochemical properties of these N-doped PAHs were investigated, which demonstrated the capability of N-doping to adjust optical and electronic properties and alter the LUMO energy level., Published by RSC, Cambridge

Chemical science 14(1), 54-60 (2022). doi:10.1039/D2SC05959B, Published by RSC, Cambridge

Three binary charge-transfer (CT) compounds resulting from the donor 2,2′ : 6′,2′′ : 6′′,6-trioxotriphenylamine (TOTA) and the acceptors F4TCNQ and F4BQ and of a pyrene-annulated azaacene (PAA) with the acceptor F4TCNQ are reported. The identity of these CT compounds are confirmed by single-crystal X-ray diffraction as well as by IR, UV-vis-NIR and EPR spectroscopy. X-ray diffraction analysis reveals a 1 : 1 stoichiometry for TOTA·F4TCNQ, a 2 : 1 donor : acceptor ratio in (TOTA)2·F4BQ, and a rare 4 : 1 stoichiometry in (PAA)4·F4TCNQ, respectively. Metrical parameters of the donor (D) and acceptor (A) constituents as well as IR spectra indicate full CT in TOTA·F4TCNQ, partial CT in (TOTA)2·F4BQ and only a very modest one in (PAA)4·F4TCNQ. Intricate packing motifs are present in the crystal lattice with encaged, π-stacked (F4TCNQ-)2 dimers in TOTA·F4TCNQ or mixed D/A stacks in the other two compounds. Their solid-state UV-vis-NIR spectra feature CT transitions. The CT compounds with F4TCNQ are electrical insulators, while (TOTA)2·F4BQ is weakly conducting. published

RSC Advances 13(4), 2530-2537 (2023). doi:10.1039/D2RA06928H, Published by RSC Publishing, London

Americium separation from high level nuclear waste can provide certain benefits such as reducing the long-term heat generation or the possibility of re-use as fuel in innovative reactors. The separation is carried out through solvent extraction. Among commonly used ligands, diglycolamide (DGA) derivatives have shown high distribution ratios for trivalent lanthanides (Ln(III)) and actinides (An(III)). Recently, different diastereomers of DGAs with substitutions in the backbone have shown an inverse selectivity for Am over Cm, in comparison with commonly used DGAs. Hence, we synthesised, characterized, and tested novel syn- and anti-diastereomers of tetra-n-octyl and tetra-n-decyl DGAs with two propyl and ethyl-methyl substituents at the backbone methylene carbon atoms. The distribution ratios for An(III) and Ln(III) were found to be generally lower than for the unsubstituted parent molecules due to steric hindrance. On the other hand, 239Pu was much better extracted. All tested ligands showed the inverse selectivity for Am with an Am/Cm separation factor (SFAm/Cm) around 1.5. Finally, slope analysis confirmed a 1:3 metal:ligand ratio for the DGA complexes.

RSC Advances 13(21), 14565 - 14574 (2023). doi:10.1039/D3RA02476H, The identification of fundamental relationships between atomic configuration and electronic structure typically requires experimental empiricism or systematic theoretical studies. Here, we provide an alternative statistical approach to gauge the importance of structure parameters, i.e., bond lengths, bond angles, and dihedral angles, for hyperfine coupling constants in organic radicals. Hyperfine coupling constants describe electron–nuclear interactions defined by the electronic structure and are experimentally measurable, for example, by electron paramagnetic resonance spectroscopy. Importance quantifiers are computed with the machine learning algorithm neighborhood components analysis using molecular dynamics trajectory snapshots. Atomic–electronic structure relationships are visualized in matrices correlating structure parameters with coupling constants of all magnetic nuclei. Qualitatively, the results reproduce common hyperfine coupling models. Tools to use the presented procedure for other radicals/paramagnetic species or other atomic structure-dependent parameters are provided., Published by RSC Publishing, London

Linear poly(alkylene carbonates) such as polyethylene carbonate (PEC) and polypropylene carbonate (PPC) have gained increasing interest due to their remarkable ion transport properties such as high Li+ transference numbers. The cause of these properties is not yet fully understood which makes it challenging to replicate them in other polymer electrolytes. Therefore, it is critical to understand the underlying mechanisms in polycarbonate electrolytes such as PPC. In this work we present insights from impedance spectroscopy, transference number measurements, PFG-NMR, IR and Raman spectroscopy as well as molecular dynamics simulations to address this issue. We find that in addition to plasticization, the lithium ion coordination by the carbonate groups of the polymer is weakened upon gelation, leading to a rapid exhange of the lithium ion solvation shell and consequently a strong increase of the conductivity. Moreover, we study the impact of the anions by employing different conducting salts. Interestingly, while the total conductivity decreases with increasing anion size, the reverse trend can be observed for the lithium ion transference numbers. Via our holistic approach, we demonstrate that this behavior can be attributed to differences in the collective ion dynamics.