| Akhil Tayal |
ISS Lead Beamline Scientist, Spectroscopy Program, National Synchrotron Light Source II
Brookhaven National Lab (BNL)
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Operando High Energy-Resolution X-ray Spectroscopy at the NSLS-II Inner Shell Spectroscopy Beamline |
Understanding how materials function under real operating conditions is essential for advancing catalysis, energy storage, and environmental technologies. In this talk, I will present how high energy-resolution X-ray spectroscopies (HERXS) provide detailed, element-specific insight into oxidation states, spin states, ligand environments, and metal–ligand interactions beyond what is accessible with conventional X-ray absorption spectroscopy (XAS).
I will introduce the capabilities of the Inner Shell Spectroscopy (ISS) beamline at NSLS-II (Brookhaven National Laboratory, Upton, NY), highlighting its unique instrumentation for operando HERXS measurements. I will also discuss recent developments in AI/ML-enabled real-time data analysis that accelerate mechanistic understanding and guide materials design. |
| Alan Ianeselli |
Postdoctoral Associate, Molecular Biophysics and Biochemistry
Yale University
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DreamFold: Generative World Models to dream protein folding pathways in the latent space |
While there is an abundance of static data for the structure of biological macromolecules, the amount of data regarding their folding mechanisms and dynamics is scarce, posing a challenge to the training of AI models. World Models can come in handy in this regard. From limited data, they can build a latent, approximated representation of the spatiotemporal folding environment that can be used to train downstream AI models, overcoming data limitation issues. We developed a World Model-based generative framework to perform biomolecular simulations of protein folding. In this “hallucinated” latent environment, it becomes possible to learn policies that drive folding simulations towards a target structure with biophysical regularization contraints. Our framework can compute protein folding pathways four orders of magnitude faster (up to ~30000x) than standard MD. This model can be used to identify folding intermediates, transition states and metastable structures to be used as targets for structure-based drug discovery. |
| Arseniy Butrin |
Postdoctoral Associate, Structural Biology and Biophysics
Yale University
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Development of Ligands and Degraders Targeting MAGE-A3 |
Type I melanoma antigen (MAGE) family members are detected in numerous tumor types, and expression is correlated with poor prognosis, high tumor grade, and increased metastasis. Type I MAGE proteins are typically restricted to reproductive tissues, but expression can recur during tumorigenesis. Several biochemical functions have been elucidated for them, and notably, MAGEs regulate proteostasis by serving as substrate recognition modules for E3 ligase complexes. The repertoire of E3 ligase complexes that can be hijacked for targeted protein degradation continues to expand, and MAGE–E3 complexes are an especially attractive platform given their cancer-selective expression. Additionally, type I MAGE-derived peptides are presented on cancer cell surfaces, so targeted MAGE degradation may increase antigen presentation and improve immunotherapy outcomes. Motivated by these applications, we developed novel, small-molecule ligands for MAGE-A3, a type I MAGE that is widely expressed in tumors and associates with TRIM28, a RING E3 ligase. Chemical matter was identified through DNA-encoded library (DEL) screening, and hit compounds were validated for in vitro binding to MAGE-A3. We obtained a cocrystal structure with a DEL analog and hypothesize that the small molecule binds at a dimer interface. We utilized this ligand to develop PROTAC molecules that induce MAGE-A3 degradation through VHL recruitment and inhibit the proliferation of MAGE-A3 positive cell lines. These ligands and degraders may serve as valuable probes for investigating MAGE-A3 biology and as foundations for the ongoing development of tumor-specific PROTACs. |
| Bodan Hu |
Associate Research Scientist, Cell Biology
Yale University
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Molecular insights into bulk lipid transport from structural studies of the bridge-like protein VPS13A complexed with the scramblase XKR1 |
In eukaryotes, bridge-like lipid-transfer proteins (BLTPs) are central in mediating vesicle-independent lipid transfer between organelles. BLTPs span the cytosolic space between organelles at contact sites, featuring hydrophobic channels for lipids to travel between membranes. How BLTPs cooperate with partner proteins to orchestrate lipid delivery remains mysterious. Here we used cryo-electron microscopy to visualize a complex comprising the prototypical BLTP VPS13A and the plasma membrane localized scramblase XKR1 at near-atomic resolution. VPS13A interacts with XKR1 via its PH-domain, priming VPS13A’s bridge-like lipid-transfer domain to deliver lipids directly to the cytosolic leaflet of the acceptor membrane. In molecular dynamics simulations, such arrangement allows for robust lipid transfer, accelerated by membrane properties. Newly delivered lipids can then be equilibrated between leaflets of the membrane bilayer by the scramblase, allowing for membrane growth. Mechanistic insights regarding lipid delivery by VPS13A are directly applicable to all VPS13 proteins and all BLTP family members more broadly. |
| Dana Dayan |
PhD Candidate in Computational Biology & Biomedical Informatics
Yale University
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DEPP: Predicting Drug Binding Affinity Through Dynamic Protein Conformational Ensembles |
In recent years, protein structure prediction has advanced dramatically. However, current models treat proteins as static structures, predicting only the most probable conformation rather than accounting for conformational ensembles. Consequently, downstream applications such as protein-ligand binding affinity prediction are biased toward interactions with a single structure, overlooking the dynamic nature of protein function. To address this limitation, we introduce DEPP (Dynamic Embedding Property-Based Predictor), which leverages evolutionary-scale embeddings (ESM-2) to represent protein conformational ensembles and predict ensemble-specific binding affinities.
DEPP models protein dynamics as a continuous stochastic process in latent space using a Langevin-type stochastic differential equation. The model learns trajectory-dependent drift and diffusion terms directly from molecular dynamics simulations, capturing how proteins evolve and transition between conformational states. This probabilistic formulation enables DEPP to generate embeddings representing physically plausible conformational ensembles while simultaneously predicting functional properties for each sampled state.
Our model achieves rapid binding affinity predictions with a median accuracy of 0.63 kcal/mol MAE„ approaching chemical accuracy while reducing computational time from days to minutes compared to molecular dynamics simulations. Furthermore, we demonstrate that intrinsically disordered regions (IDRs) exhibit significantly greater variability in protein-ligand binding affinity compared to ordered proteins (p = 7.6 × 10⁻³), highlighting that binding specificity emerges from conformational ensembles rather than single static structures. Our findings suggest that ensemble-based approaches are essential for accurate prediction of protein-ligand interactions, particularly for dynamic or disordered proteins.
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| Du (Devin) Chen |
PhD Candidate, Chemical & Environmental Engineering
Yale University
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Measuring Anisotropic Thermal Transport in Single-crystal 2D Hybrid Perovskite Superlattices |
Two-dimensional (2D) organic–inorganic hybrid metal halide perovskites (MHPs) represent an emerging class of materials combining remarkable optoelectronic performance with structural tunability. Their wide design space—spanning organic spacer length and type, and inorganic quantum-well thickness—offers versatile control over crystal structure, interlayer spacing, and octahedral connectivity. Yet, the influence of these structural parameters on thermal transport remains poorly understood. Reports to date have shown conflicting trends in cross-plane thermal conductivity with spacer chemistry and layer thickness, while systematic studies of in-plane transport are largely absent due to limitations of existing thermometry techniques.
Here, we present a vibrational-pump visible-probe (VPVP) platform as a transducer-free technique for rapid and direct tracking of thermal transport in 2D-MHPs with high spatiotemporal resolution. The VPVP technique leverages the intrinsic thermoreflectance near the excitonic resonance and vibrational absorption in the mid-infrared (MIR) to impulsively heat the lattice via a resonant MIR pump and monitor subsequent temperature evolution using a delayed visible probe over nanosecond–microsecond timescales.
Using VPVP, we quantitatively resolved anisotropic thermal transport in single-crystal 2D MHPs with systematically varied octahedral-layer thicknesses and organic-spacer chemistries. Our results revealed superlattice-like thermal behaviors of 2D-MHPs, where (1) the cross-plane thermal conductivity increases monotonically with reduced organic-inorganic interfacial density, via thicker octahedral layer or longer organic spacers, and (2) the in-plane thermal transport improves with thicker octahedral slabs but decreases with lengthened alkylammonium spacers. A modest (<2.7) and progressively decreasing anisotropy ratio with decreasing interface density was observed, further explained by the first-principles calculation highlighting strong lattice anharmonicity and significant four-phonon scattering contributions.
This work establishes VPVP as a powerful non-contact tool of nanoscale heat transport and provides new insight into the structure–thermal transport relationships governing 2D hybrid perovskites.
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| Gozde Ustuner |
Researcher, Surface Electrochemistry and Electrocatalysis Group, Chemistry Division
Brookhaven National Lab (BNL)
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MOF-supported Intermetallic Pt-based Electrocatalysts for the Oxygen Reduction Reactions |
Fuel cells are a promising technology for converting chemical feedstocks into clean energy; however, their widespread deployment is limited by the sluggish kinetics of the oxygen reduction reaction (ORR) and the high platinum (Pt) loading required at the cathode. These challenges significantly impact both efficiency and cost. This research presents a strategy for developing low-Pt-content electrocatalysts for ORR in proton-exchange membrane fuel cells (PEMFCs), aiming to reduce cost while improving catalytic activity, durability, and long-term operational stability.
Pt-based electrocatalysts incorporating non-noble transition metals (M = Ni, Fe, Co) have demonstrated enhanced ORR kinetics through electronic and strain effects while lowering overall Pt usage. Among these systems, Pt–Ni catalysts have attracted particular attention because of their high activity, durability, and suitability for practical fuel cell operating conditions. The work presented here focuses on optimizing Pt–Ni catalysts through nitrogen (N) doping with a novel catalyst support.
Catalyst supports play a critical role in determining electrocatalyst performance, influencing activity, stability, and resistance to degradation. Beyond conventional carbon supports, metal–organic frameworks (MOFs) have emerged as promising alternatives due to their high surface area, tunable porosity, and structural versatility. Zeolitic imidazolate frameworks (ZIFs), a subclass of MOFs, possess zeolite-like structures with excellent chemical and thermal stability, making them attractive materials for ORR catalyst development.
In this study, ZIF-67 was used as a precursor to synthesize N-doped carbon supports for ordered Pt-based intermetallic electrocatalysts. Two catalysts, PtNiCoN-NC and PtNiN-Mn/NC, were synthesized and evaluated using electrochemical methods. Structural and morphological characterization was carried out using scanning transmission electron microscopy (STEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD), while local atomic structures were probed using in situ X-ray absorption spectroscopy (XAS). Both electrocatalysts demonstrated enhanced ORR activity and excellent stability, highlighting the superior characteristic of MOF-derived N-doped carbon support for electrocatalyst design and commercialization.
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| Jose Rodriguez |
Interim Chair Chemistry Division, Catalysis: Reactivity and Structure Group, Chemistry Division
Brookhaven National Lab (BNL)
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Fundamental studies in C1 Catalysis |
Fundamental studies in C1 Catalysis |
| Kirill Grushin |
Research Scientist, Cell Biology
Yale University
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Structural insights into Munc13-1 self-assemblies on lipid bilayers from cryo-electron tomography. |
Munc13-1 is a key chaperone in synaptic vesicle docking and priming, tethering vesicles to PIP2-enriched plasma membrane microdomains at the active zone and templating the SNARE proteins assembly (Syntaxin1A, VAMP2, SNAP25). Despite the critical role, the structural insights behind the functioning of Munc13 remain unclear due to conformational flexibility and the requirement for lipid membranes for its function.
We recently demonstrated that the functional core of Munc13-1 (Munc13C: C1–C2B–MUN (Δ1408–1452, EF)–C2C, ~133 kDa) assembles into a 2D lattice between two lipid bilayers when incubated with negatively charged lipid vesicles, mimicking the synaptic active zone. Using cryo-electron tomography and subtomogram averaging we resolved the lattice at sub-nanometer resolution, revealing two membrane-bound conformations of Munc13C: an “open” form that organizes into trimers and a “closed” form that assembles into hexamers, with trimers bridging hexamers into an extended network. Mutations disrupting the oligomerization interfaces hampered vesicle docking and fusion in vitro and impaired synaptic transmission in C. elegans, underscoring the functional importance of Munc13-1 oligomerization. Furthermore, mutations targeting the hexamer supporting interface produced alternative crystal forms, revealing an additional “slanted” orientation of the open conformation, possibly reflecting a stage of Munc13-driven priming. In the slanted state, the positively charged α-helical region of the linker between C1 and C2B domains interacts with the lipid membrane surface along with C2B domain. Charge-neutralizing mutations in this region caused a dramatic reduction in vesicle docking and severely impaired Ca²⁺-triggered fusion in vitro.
Together, these findings highlight the essential role of Munc13-1 oligomerization and conformational switching in synaptic vesicle docking and priming, supporting a stepwise model of Munc13-1 action and offering a structural framework for dissecting the molecular basis of neurotransmitter release.
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| Marisa Barilla |
PhD Candidate, Chemistry
Yale University
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Protective Mechanisms of CAHS IDPs in Tardigrades |
Tardigrades are microscopic animals that tolerate an array of stressors, including radiation, high and low temperatures, and desiccation. Although the exact mechanisms of extreme tolerance are poorly elucidated, tardigrades produce bioprotectant molecules with properties that may be exploited for biomedical and pharmacological applications. A family of tardigrade-specific intrinsically disordered proteins (IDPs), cytoplasmic abundant heat soluble (CAHS) proteins, is known to protect and preserve cytosolic biomolecules while tardigrades are in a desiccated state. Intriguingly, tardigrades that constitutively express CAHS at high levels are more tolerant than tardigrades in which stress triggers CAHS expression. Here, we investigate the protective mechanism of CAHS in vivo in constitutive and stress-induced CAHS expressing tardigrades R. varieornatus and H. exemplaris, respectively. Tardigrades are transfected with a FRET-labeled crowding sensor, CrH2, under a promoter for expression of the transgene in CAHS expressing tissues. Using confocal microscopy, we quantify FRET to assess crowding and confinement of the crowding sensor in living tardigrades before and after desiccation as well as through the rehydration process. In hydrated conditions, epidermal cells are more crowded in constitutive CAHS expressing tardigrades compared to tardigrades that require a preconditioning period. After desiccation, the resultingly high concentrations of CAHS in both species induce confinement that is consistent with hydrogel formation. Complementary in vitro protein folding experiments interpret in vivo results. Low concentrations of CAHS promote more extended unfolded states and protect against aggregation, while the same proteins are stabilized by confinement in CAHS gels. Taken together, these in vitro and in vivo results support a mechanism where confinement by CAHS hydrogels stabilize proteins in both tardigrade species during desiccation. They further suggest that in hydrated environments CAHS protects proteins against aggregation through noncovalent interactions, allowing for more robust response to stress. These mechanisms may inform TDP-based strategies for the preservation of pharmaceuticals and biomaterials. |
| Matthew Bird |
Chemist, Electron- and Photo-Induced Processes for Molecular Energy Conversion, Chemistry Division
Brookhaven National Lab (BNL)
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Pulse Radiolysis at BNL for Photochemistry & Electrochemistry |
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| Matthew Emerson |
Research Associate Chemistry, Electron- and Photo-Induced Processes for Molecular Energy Conversion Group, Chemistry Division
Brookhaven National Lab (BNL)
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EPIP: Coupling Pulse Radiolysis with Classical and Ab-Initio Molecular Dynamics to Understand Reactivity and Structure in Ionic Liquids and Molten Salts |
The EPIP group advances mechanistic understanding of complex condensed-phase chemistry by integrating time-resolved experiments with multiscale simulation. Core capabilities include picosecond electron pulse radiolysis, rigorous data reduction and kinetic analysis, classical molecular dynamics with polarizable ion models, and ab-initio molecular dynamics for electronic-structure–informed interpretation of transient species and reaction pathways. This presentation highlights representative published and in-progress results in room-temperature ionic liquids and high-temperature molten salts. Emphasis is placed on connecting experimentally accessible observables—transient absorption spectra, kinetics, and dose-dependent yields—with simulation-derived descriptors such as solvation structure, transport properties, and free-energy landscapes. The integrated workflow enables quantitative links between local coordination environments and reactivity, supports systematic model refinement and parameterization across chemistries, and provides a foundation for predictive control of radiolytic processes in technologically relevant ionic media. At the end, a brief discussion of plans for developing an agentic framework for optimizing accelerator magnet and phase settings will be discussed. |
| Preshit Abhyankar |
Research Associate, Artificial Photosynthesis Group, Chemistry Division
Brookhaven National Lab (BNL)
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Mn(I) complexes with dicationic bipyridine ligands for aqueous electrochemical carbon dioxide reduction |
The development of efficient (electro)chemical strategies for carbon dioxide (CO₂) reduction is critical for the sustainable production of carbon-neutral fuels. First-row transition-metal catalysts, particularly Mn and Co based complexes, have emerged as promising candidates. However, key challenges remain, including the controlled delivery of multiple equivalents of electrons and protons and maintaining catalyst stability under sustainable, environmentally benign conditions. Aqueous CO₂ reduction systems and selective access to molecules beyond two-electron reduction products, such as methanol and methane, are of particular interest. Previous work from our group demonstrated that rhenium complexes with dicationic substituted bipyridine ligands enable rapid electrocatalytic CO₂-to-CO conversion in acetonitrile. We have extended this platform to aqueous electrochemical CO₂ reduction at neutral or mildly basic pH. Addionially, we have also developed Mn(I) analogues for aqueous electrocatalytic CO₂-to-CO reduction. Albeit slower than the Re-analogues, these Mn(I) electrocatalysts enable the reduction at a significantly lower overpotential. Additionally, the lessons learnt during the development of these Mn(I)-analogues have been used to guide in designing electrocatalysts to enable CO-to-methanol reduction. These findings are presented herein. |
| Samira Heydari |
Postdoctoral Associate. Microbial Pathogenesis
Yale University
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Structural dynamics and activation of the Dot/Icm T4SS revealed by in situ CryoEM |
The Legionella pneumophila Dot/Icm type IV secretion system (T4SS) translocates hundreds of effector proteins into host cells and is essential for intracellular replication and disease progression. While the inactive architecture of the complex has been resolved at high resolution, the structural basis of the active state and outer-membrane gating has remained unclear for several years. Using cryo–electron tomography (cryoET) and in situ cryo–electron microscopy (cryoEM), we defined the structural transitions underlying activation of the Dot/Icm T4SS within intact bacteria. Our study revealed distinct major populations corresponding to partially assembled, fully assembled inactive, and secretion-competent conformations. The active complex exhibits coordinated remodeling across the central channel and outer membrane complex, forming a continuous cylindrical conduit spanning the bacterial envelope. Activation is also accompanied by formation of an extracellular protrusion at the tip of the channel; cryoET analysis of infected macrophages further shows that this protrusion mediates interaction with the host cell. Focused classification of the secretion-competent particles resolved distinct luminal states, including a fully open conduit and a configuration containing additional central density consistent with transient substrate engagement. A central feature of the active state is pronounced radial expansion of the dome region formed by the C-terminal domain of DotG, which spans the periplasm. This activation-dependent dilation enlarges the outer-membrane aperture and aligns geometrically with expansion of the periplasmic conduit, establishing a continuous envelope-spanning pathway. Together, these findings support a sequential model in which assembly of the core scaffold is followed by activation-dependent remodeling of the DotG outer-membrane gate and channel expansion, resulting in a translocation-competent state. This work provides a structural framework linking assembly, activation, and host engagement in a complex multi-protein T4SS. While the inactive architecture has defined candidate channel components, further studies are needed for the molecular characterization of the channel components in the active state. |
| Sean McSweeney |
Director, Biological, Environmental, & Planetary Sciences Division, National Synchrotron Light Source II
Brookhaven National Lab (BNL)
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The Center for Biomolecular Structure (CBMS) |
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| Vivian Stojanoff |
Physicist, Structural Biology Program, National Synchrotron Light Source II
Brookhaven National Lab (BNL)
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CBMS access, training and outreach: Opportunities for training and Collaborations |
The Center for Biomolecular Structure (CBMS) supports a broad spectrum of scientific research, spanning structural biology to multimodal imaging of environmental and biologically relevant samples. Its mission is to provide researchers with state-of-the-art instrumentation, advanced analytical capabilities, and collaborative platforms to address major scientific challenges of the coming decade. The User, Training, and Outreach Core (UTOC) strengthens the missions of the National Institutes of Health and the Office of Biological and Environmental Research by fostering user engagement, education, and community-building initiatives.
The CBMS training program emphasizes hands-on workshops and virtual tutorials focused on data analysis software and experimental methodologies. These efforts are complemented by beamline-specific manuals, comprehensive documentation, and direct guidance during beam time, ensuring that users are well supported from proposal development through data interpretation.
CBMS staff also collaborate closely with Brookhaven National Laboratory Workforce Development and Science Education to mentor high school, undergraduate, graduate, and postdoctoral trainees.
At the undergraduate level, students participate in U.S. Department of Energy programs such as the DOE Science Undergraduate Laboratory Internships, which provide immersive research experiences within the national laboratory environment. These internships introduce students to advanced instrumentation, interdisciplinary collaboration, and career pathways in science and engineering.
For graduate students, the DOE Office of Science Graduate Student Research Program supports those who wish to apply one or more specialized techniques available at national laboratories to strengthen and expand research developed at their home institutions. This program enables doctoral candidates to complement their thesis work by accessing unique facilities, expertise, and methodologies that enhance the depth and impact of their graduate studies. |
| Yunyang Li |
Graduate Student, Computer Science
Yale University
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Enhancing the Scalability and Applicability of Kohn-Sham Hamiltonians for Molecular Systems |
Density Functional Theory (DFT) is a pivotal method within quantum chemistry and materials science, with its core involving the construction and solution of the Kohn-Sham Hamiltonian. Despite its importance, the application of DFT is frequently limited by the substantial computational resources required to construct the Kohn-Sham Hamiltonian. In response to these limitations, current research has employed deep-learning models to efficiently predict molecular and solid Hamiltonians, with roto-translational symmetries encoded in their neural networks. However, the scalability of prior models may be problematic when applied to large molecules, resulting in non-physical predictions of ground-state properties. In this study, we generate a substantially larger training set (PubChemQH) than used previously and use it to create a scalable model for DFT calculations with physical accuracy. For our model, we introduce a loss function derived from physical principles, which we call Wavefunction Alignment Loss (WALoss). WALoss involves performing a basis change on the predicted Hamiltonian to align it with the observed one; thus, the resulting differences can serve as a surrogate for orbital energy differences, allowing models to make better predictions for molecular orbitals and total energies than previously possible. WALoss also substantially accelerates self-consistent-field (SCF) DFT calculations. Here, we show it achieves a reduction in total energy prediction error by a factor of 1347 and an SCF calculation speed-up by a factor of 18%. These substantial improvements set new benchmarks for achieving accurate and applicable predictions in larger molecular systems. |