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Item type:Publication, Access status: with files , Solvation-controlled accessibility and irreversible finalization of aminoxy intermediates in TEMPO/Benzothiadiazole nonaqueous redox flow batteries(American Chemical Society (ACS), 2026-08-19); ; ; ; Understanding how reactive intermediates form and evolve during electrochemical operation is essential for improving the stability of molecular energy-storage systems. Here, we investigate the degradation chemistry of an all-organic nonaqueous redox flow battery based on a nitroxide catholyte and a benzothiadiazole anolyte. By combining electrochemical analysis, full-cell cycling experiments, and molecular dynamics simulations, we reveal how the solvation environment governs both the electrochemical accessibility and the chemical fate of transient reduced intermediates. To rationalize these effects, we introduce a chemically informed framework that decouples electrochemical exposure of parasitic pathways from the probability that such events culminate in irreversible product formation. This minimal model quantitatively captures the relationship between coulombic efficiency and capacity loss across a range of ionic liquid electrolytes, providing a unified description of degradation behavior under realistic operating conditions. Molecular-level analysis further shows that electrolyte-dependent solvation and local coordination environments modulate the stabilization and reactivity of key intermediates, thereby controlling the balance between reversible redox processes and permanent inventory loss. These findings establish a direct link between electrolyte solvation structure and electrochemical degradation pathways, offering a general strategy to diagnose and mitigate failure mechanisms in molecular electrochemical systems. More broadly, the approach provides a conceptual framework for connecting reactive intermediate chemistry with macroscopic device performance in organic energy-storage technologies.Publicationtype: Journal Article7 5 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Vibrational fingerprints of strained polymers: a spectroscopic pathway to mechanical state prediction(IOP Publishing, 2026-06-01); ; ; ; The vibrational response of polymer networks under load provides a sensitive probe of molecular deformation and enables non-destructive diagnostics. Machine-learned force fields reproduce these spectroscopic fingerprints with quantum-level fidelity in realistic epoxy thermosets. Using MACE-OFF23 molecular dynamics, the experimentally observed redshifts of para-phenylene stretching modes under tensile load are captured, in contrast to predictions from the harmonic OPLS-AA model. The shifts correlate with molecular elongation and alignment, consistent with Badger’s rule, thereby establishing a direct link between vibrational features and local stress. Infrared intensities are predicted through a symmetry-adapted dipole moment model trained on representative epoxy fragments, enabling quantitative validation of strain-dependent responses. The combined approach yields chemically accurate and computationally efficient predictions of vibrational spectra under deformation. These results identify vibrational fingerprints as predictive markers of mechanical state in polymer networks and outline a spectroscopic route to stress mapping and structural-health diagnostics in advanced materials.Publicationtype: Journal Article48 16 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Network topology governs cryogenic mechanical response in isocyanate-modified epoxy networks(American Chemical Society, 2026-05-11); ; ; High-performance epoxy-based polymers are increasingly deployed in space applications, where cryogenic service conditions impose stringent demands on mechanical performance over a wide temperature range. Modification of epoxy resins is commonly employed to improve fracture toughness and to mitigate brittle behavior. In this study, isocyanate-modified epoxy networks were investigated by combining molecular dynamics simulations with dynamic mechanical thermal analysis. Structural descriptors such as radius of gyration and hydrogen-bond statistics were correlated with elastic and thermal properties to establish molecular-level structure–property relationships. The simulations reveal homogeneous chain extension for systems containing up to 20% isocyanate, whereas further addition contributes little to backbone elongation. Hydrogen bonds provide a secondary stabilization mechanism at low temperatures, but selectively disabling hydrogen bonding demonstrates that covalent network topology dominates stiffness. The β-transition is consistently identified in simulation and experiment and shifts to lower temperature upon isocyanate incorporation. The corresponding transition temperature Tβ marks a change in the dominant stiffening mechanism. Analysis of molecular fluctuations shows that below Tβ stiffness is governed primarily by network compactness, while above Tβ enhanced segmental mobility leads to accelerated softening despite hydrogen-bond formation.Publicationtype: Journal Article75 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Temperature-dependent capacitance of the electrical double layerWe use atomistic simulations to study the electrical double layer (EDL) at an electrode–electrolyte interface at different temperatures. For a constrained electrode charge, the potential drop over the EDL increases with temperature, a phenomenon known as the thermal voltage rise (TVR). Prior continuum models attributed TVR to expansion of the EDL with increasing temperature; conversely, our simulations with aqueous, organic, and ionic liquids show that the EDL does not expand but that the TVR is caused by a decrease in interfacial permittivity with increasing temperatures.Publicationtype: Journal Article57 62 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Probing the influence of sulfur–aromatic interactions on the electronic structure of gas-phase peptides(Wiley, 2026-04-02); ; ; ; Girod, MarionNon-covalent sulfur–aromatic ((Formula presented.)) interactions play a crucial role in stabilizing the structure of proteins and have been associated with neurodegenerative diseases. We investigated the influence of the (Formula presented.) interaction on the electronic structure and fragmentation behavior of sequence-isomer model peptides by means of ultraviolet photodissociation (UVPD) and near-edge x-ray absorption mass spectrometry (NEXAMS). The studies revealed distinct fragmentation behavior for one of the model peptides under both valence and core–shell electronic excitation, with characteristic fragmentation channels that serve as potential fingerprints of sulfur–aromatic interactions. Moreover, core–shell excitations at the carbon K-edge revealed significant shifts between the (Formula presented.) peptide and the control peptides in the aromatic (Formula presented.) transitions, indicating changes in the electronic structure due to (Formula presented.) interactions. Enhanced sampling molecular dynamics and quantum mechanical calculations reveal the influence of the sulfur orientation, providing insights into the fundamental nature of (Formula presented.) interactions.Publicationtype: Journal Article23 11 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Defect migration in supercrystalline nanocomposites(American Chemical Society (ACS), 2025-12-16); ; ; ; Supercrystalline nanocomposites (SCNCs) are nanostructured hybrid materials with a variety of unique functional properties. Given their periodically arranged building blocks, they also offer interesting parallels with crystalline materials. They can be processed in multiple forms and at different scales, and cross-linking their organic ligands via heat treatment leads to a boost of their mechanical properties. This study shows, via X-ray and in situ scanning transmission electron microscopy (STEM) analyses, how each of these processing steps plays a distinct role in the generation, migration, interaction, and healing of supercrystalline defects. Pressing of SCNCs into bulk pellets leads to a distortion of the otherwise fcc superlattice, while emulsion-templated self-assembly yields supraparticles (SPs) with stacking faults and size-dependent symmetries. Heat treatment at the same temperatures as those applied for the organic cross-linking has significant effects on planar defects. Stacking faults migrate and get healed, as also confirmed via molecular dynamics simulations, and intersupercrystalline “grain” boundaries migrate via anisotropic motion of disconnections. These rearrangements of defects at the supercrystalline scale (tens of nanometers) in nanocomposites with high mechanical properties (compressive strength of 100–500 MPa) provide insights into the formation and evolution of ordered assemblies of functionalized nanoparticles.Publicationtype: Journal Article43 15 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Capacitive deionisation for water desalination review: experimental and simulation(Taylor & Francis, 2025-10-28); ; ; Capacitive Deionization (CDI) has emerged as an energy-efficient and environmentally friendly technology for water desalination. This review provides a comprehensive analysis of CDI, covering both experimental and simulation approaches. It introduces the background, definition, and diverse applications of CDI, from water desalination to environmental monitoring and resource recovery. The review highlights CDI’s advantages, such as low energy consumption and operational simplicity, as well as its limitations, particularly its design-specific operating window favoring low-to-moderate salinity waters and sensitivity to organic-rich conditions. Strategies such as hybrid CDI systems and electrode surface functionalization are discussed to mitigate these challenges. Key working principles and advancements, including innovations in electrode materials, synthesis methods, and reactor design, are examined to improve ion removal efficiency, selectivity, energy use, and system durability. Material modification strategies are presented in the context of structure–performance relationships, emphasizing rational design principles. The review also explores simulation methods, including reactor modeling, computational fluid dynamics, molecular dynamics, and numerical approaches, and machine learning highlighting their synergy with experiments in optimizing CDI performance and guiding scale-up. Coupling CDI with other systems and its applications in water purification, particularly for ion and organic compound removal are also discussed. Finally, challenges in both experimental and simulation efforts, such as material cost, model complexity, computational demands, and scalability, are discussed. While CDI shows promise for sustainable water desalination and resource recovery, further research on hybrid configurations, predictive modeling, and pilot-scale validation is needed to address its limitations and enable large-scale adoption.Publicationtype: Review Article80 20 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Effect of anion hydrophobicity on the oxidation of ferrocene-terminated monolayersSelf-assembled monolayers (SAMs) terminated with ferrocene ((Formula presented.)) moieties are a popular model system for electron transfer processes at solid-liquid interfaces. Numerous experimental studies have found a correlation between the hydrophobicity of anions in the electrolyte and the redox potential. In this computational study, the redox potential is calculated for various anion species and SAM configurations using classical molecular dynamics. Thermodynamic integration and the constrained charge method are used to determine the redox potential as the free energy change associated with electron transfers from the (Formula presented.) moieties to the electrodes. The results show the anticipated lower redox potentials for hydrophobic anions and allow the study of changes at the solid-liquid interface at the atomistic level.Publicationtype: Journal Article57 55 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Atomistic modeling of functionalized magnetite surfaces with oxidation states(American Chemical Society (ACS), 2025-07-03); ; Understanding the atomic structure of magnetite-carboxylic acid interfaces is crucial for tailoring nanocomposites involving this interface. We present a Monte Carlo (MC)-based method utilizing iron oxidation state exchange to model magnetite interfaces with tens of thousands of atoms, scales typically inaccessible by electronic structure calculations. Charge neutrality is ensured by the oxidation of Fe ions. The MC approach allows magnetite to adapt to its environment at interfaces without requiring interface-specific rescaling of force-field parameters. This enables a simple, versatile method. By comparing adsorption sites, layer distances, and bond lengths with results from electronic structure calculations and experiments, we validated the accuracy of our method. We found that the oxidation state distribution and, consequently, binding site preference depend on coverage and surface thickness, with a critical thickness signaling the transition from layered to bulk-like oxidation states. The method ensures seamless compatibility with popular biomolecular force fields providing transferability and simplifying the study of magnetite interfaces in general.Publicationtype: Journal Article18 18 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Smart reaction templating: a graph-based method for automated molecular dynamics input generationAccurately modeling chemical reactions in molecular dynamics simulations requires detailed pre- and postreaction templates, often created through labor-intensive manual workflows. This work introduces a Python-based algorithm that automates the generation of reaction templates for the LAMMPS REACTION package, leveraging graph-theoretical principles and subgraph isomorphism techniques. By representing molecular systems as mathematical graphs, the method enables the automated identification of conserved molecular domains, reaction sites, and atom mappings, significantly reducing manual effort. The algorithm was validated on three case studies: poly addition, poly condensation, and chain polymerization, demonstrating its ability to map conserved domains, identify reaction-initiating atoms, and resolve challenges such as symmetric reactants and indistinguishable atoms. Additionally, the generated templates were optimized for computational efficiency by retaining only essential reactive domains, ensuring scalability and consistency in high-throughput workflows for computational chemistry, materials science, and machine learning applications. Future work will focus on extending the method to mixed organic-inorganic systems, incorporating adaptive scoring mechanisms, and integrating quantum mechanical calculations to enhance its applicability.Publicationtype: Journal Article25 14