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We investigate the ultrafast spin dynamics of a Janus NiBrCl bilayer under femtosecond laser excitation using real-time time-dependent density functional theory. The system exhibits pronounced nonequilibrium spin behavior within 50 fs, characterized by rapid demagnetization of both Ni sublattices and a transient breakdown of antiferromagnetic compensation. The Br atoms show spin dynamics closely following the Ni sites, indicating strong p-d hybridization and ligand-mediated spin polarization. In contrast, the Cl sublattice exhibits a strongly site-dependent response: the interfacial Cl1 atom remains nearly inactive, while the outer-surface Cl2 atom hosts a significant negative spin accumulation despite weak charge transfer and negligible conduction-band occupation. Real-space magnetization density analysis further confirms a highly anisotropic spin redistribution, revealing that ultrafast magnetic dynamics are governed by Ni-Br coherent demagnetization and Janus-induced surface-selective spin accumulation at the outer Cl layer. These results highlight the crucial role of structural asymmetry in controlling ultrafast spin transport in two-dimensional magnetic materials.

As a next-generation energy storage technology, seawater-based zinc-air batteries (SZABs) hold great promise for efficiently utilizing marine energy. However, oxygen electrocatalysis at the air cathode remains severely impeded by inherent sluggish kinetics and detrimental Cl- interference in chloride-rich electrolytes. To address this bottleneck, we report an electronic metal-support interactions (EMSIs)-driven spin-state engineering strategy, wherein Fe-NC support is integrated with low-loading PtFeCu alloy nanoparticles. Experimental and theoretical studies reveal that the EMSIs trigger a critical spin-state transition of Fe-N4 centers from a low-spin (t2g 6 eg 0) to an intermediate-spin (t2g 5 eg 1) configuration, which effectively adjusts Fe-O d-p orbital interactions and mitigates Cl- binding. The resulting catalyst delivers remarkable bifunctional activity and long-term stability in alkaline seawater, delivering a high oxygen reduction reaction (ORR) half-wave potential of 0.909 V, a low oxygen evolution reaction (OER) overpotential of 346 mV at 10 mA cm- 2, and a narrow voltage gap of only 0.67 V. The assembled SZABs exhibit excellent power density and durability, demonstrating practical potential for maritime emergency and wearable energy devices. This work establishes spin-state engineering as a potent paradigm for developing efficient and chloride-tolerant seawater electrocatalysts, and offers mechanistic insights into spin-state-dependent catalysis.

Non-radiative energy loss in high-efficiency organic solar cells (OSCs) is closely associated with triplet-mediated recombination involving triplet charge-transfer (3CT) states. Here, rather than suppressing this pathway solely through excited-state energetic engineering, we explore a spin-manipulation strategy using intrinsically open-shell non-fullerene acceptors (NFAs) as spin-active guest acceptors in OSC blends. Two (thio)barbituric acid-terminated open-shell NFAs, MAZ-1 and MAZ-2, were incorporated into D18:N3 solar cells. Electron spin resonance (ESR), variable-temperature ESR, and variable-temperature 1H NMR measurements confirm their open-shell character and thermally accessible triplet states. Upon MAZ incorporation, the ternary devices exhibit weakened high-field magneto-photocurrent responses and accelerated decay of long-lived CT states, consistent with modulated CT-state spin evolution and suppressed triplet-related recombination. Consequently, the non-radiative energy loss is reduced by up to ∼20 meV, accompanied by enhanced charge transport, improved morphology, and a power conversion efficiency increase from 18.52% to 20.23%. This work establishes open-shell guest acceptors as an intrinsic spin-active platform for manipulating CT-state spin dynamics and reducing non-radiative recombination losses in OSCs.

Singlet fission (SF), which has applications in areas ranging from solar energy to quantum information, relies critically on transitions within a multi-spin manifold. These transitions are driven by fluctuations in the spin-spin exchange interaction, which have been linked to changes in nuclear geometry or exciton migration. While simple calculations have supported this mechanism, to date, limited efforts have been made to model realistic fluctuations, which are informed by the actual structure and properties of physical materials. In this paper, we develop a modular computational pipeline for calculating SF spin dynamics by way of electronic structural calculations, molecular dynamics, and numerical models of spin dynamics. The outputs of this pipeline aid in the interpretation of measured spin dynamics and allow us to place constraints on geometric fluctuations, which are consistent with these observations.

Spintronics represents an area of study that makes use of the spin characteristic of the electron to control the behavior of quantum electronics devices relative to the typical charge electronics. In the present study, we carried out a detailed density functional theory-based analysis on the thermodynamic and mechanical stability of half-metallic ferromagnetic NiSc2X4 (X = S and Se) spinels under the influence of pressure. The formation energies and energy minimization in both the ferromagnetic and antiferromagnetic arrangements confirm the energetic stability in the ferromagnetic state. Also, there are no imaginary frequencies in the phonon dispersion and ab initio molecular dynamics simulations, showing that these two compounds are dynamically stable. It is clear that the mechanical behavior of these two materials is quite stable since they exhibit high Poisson's ratios and high bulk-to-shear modulus ratios. The Poisson's ratios of NiSc2S4 and NiSc2Se4 are found to be 0.309 and 0.295, respectively. The B0/G ratios of NiSc2S4 and NiSc2Se4 are found to be 2.287 and 2.114, respectively. Analysis of the electronic properties indicates that an increase in the applied pressure from 0 GPa to 4 GPa leads to a significant reduction in the direct band gap. Most importantly, NiSc2S4 becomes a half-metallic ferromagnet under increased pressure. The magnetic calculations indicate a magnetic moment of 2.00 µ B per formula unit for both NiSc2S4 and NiSc2Se4, which originates mainly from the Ni atom. Also, an analysis of the thermodynamic properties of these two compounds, using the quasi-harmonic Debye approximation as implemented in the GIBBS2 program, shows lattice stiffening, phonon softening, and anharmonicity effects. The calculated entropy and Debye temperatures further confirm the stability and vibrational integrity of the system. Overall, these results show the potential of NiSc2X4 spinels in spintronic and magneto-electronic devices.

Differentiating recurrent tumor from radiation necrosis after stereotactic radiosurgery remains a challenge with conventional MRI. Fractional tumor burden, a voxel-level perfusion biomarker originally developed using DSC-MRI, characterizes intralesional perfusion heterogeneity and has demonstrated good performance and improved interrater agreement in diagnostic interpretations over conventional perfusion metrics. We evaluated arterial spin labeling-derived fractional tumor burden for distinguishing tumor recurrence from radiation necrosis in treated brain metastases. This retrospective study included 86 patients with 102 brain metastases (68 radiation necrosis, 34 tumor) evaluated with arterial spin labeling-MRI after stereotactic radiosurgery. Ground truth was based on histopathology or clinico-radiologic follow-up. The primary endpoint was fractional tumor burden-high voxel percentage (absolute and normalized). Secondary endpoints included fractional tumor burden-low, mean CBF, maximum CBF, and delta T1. Absolute CBF thresholds of ≤50 and ≥80 mL/100 g/min and normalized thresholds of ≤1.0 and ≥1.4 were defined a priori from prior histopathology-informed data. Diagnostic performance was assessed by receiver operating characteristic analysis and DeLong testing. Between-group comparisons used Mann-Whitney U tests; generalized linear mixed-effects models assessed logistic regression. Normalized fractional tumor burden-high demonstrated good discrimination of tumor from radiation necrosis, with area under the curve 0.81 (95% CI 0.71-0.90), sensitivity 0.79 (95% CI 0.63-0.94), specificity 0.74 (95% CI 0.61-0.86), PPV 0.60 (95% CI 0.43-0.77), and NPV 0.88 (95% CI 0.77-0.96), numerically outperforming absolute fractional tumor burden-high (area under the curve 0.75; 95% CI 0.66-0.84), although the difference was not significant (P = 0.22). Secondary arterial spin labeling-derived metrics demonstrated comparable performance (area under the curves = 0.79-0.83). Normalized fractional tumor burden-high significantly outperformed delta T1 (change in area under the curve = 0.19; 95% CI 0.05-0.31; P = 0.004). Logistic regression confirmed a monotonic association between normalized fractional tumor burden-high and tumor probability (OR = 1.62 per 10% increase; 95% CI 1.33-2.38; P = 0.001). Arterial spin labeling-derived fractional tumor burden-high provides good lesion-level differentiation between recurrent brain metastases and radiation necrosis after stereotactic radiosurgery, performing comparably to conventional CBF metrics. The voxel-level approach offers a clinically interpretable perfusion biomarker suitable for post-treatment response assessment.

Photons have long been the dominant mediators of interactions in cavity quantum electrodynamics (QED), with recent advances in chiral cavities enabling directional light-matter coupling. Extending these capabilities to spin qubits, however, remains a major challenge, motivating the exploration of alternative solid-state platforms. Here, we report the experimental demonstration of a chiral magnonic cavity, where magnons-collective excitations of magnetically ordered solids-replace photons. We demonstrate strong spin-magnon coupling between [Gd(W5O18)2]9- spin qubits and antiferromagnetic magnons in the van der Waals material CrSBr, observing clear anticrossings and coherent hybridization. Crucially, we exploit the intrinsic chirality of antiferromagnetic magnons to tune the coupling strength by simply rotating an external magnetic field, dynamically controlling the magnon symmetry from linear to chiral within a single device. Our results establish magnon QED as a powerful platform for spin qubit research and introduce chirality as a control knob for information flow.

The manipulation over diverse topological matters has become a critical demand for advancing quantum devices and topological spintronics. However, such experimental demonstrations remain scarce. Here, based on a novel breathing kagome magnetic Weyl semimetal LaCrGe3, we realize a spin-rotation driven Weyl state evolution under the control of an external magnetic field. While the breathing of kagome lattice is revealed to boost the desired topologic state, the predicted Weyl points are observed around the Fermi level via angle-resolved photoemission spectroscopy, and are further corroborated by transport effects of chiral-anomaly-related negative magnetoresistance and large anomalous Hall conductivity. By rotating the external magnetic field, we demonstrated that the reorientation of magnetic moments can drive the motion of Weyl points in momentum space, which is characterized by a highly tunable angle-dependent Hall response. Our study presents a modulation of both topology and transport via spin orientation that offers fundamental insights for developing next-generation spin-based functional devices based on topological physics.

Co0.6Mg0.4Cr x Fe2-x O4 (x = 0.0-0.4) spinel ferrites are successfully synthesized via a sol-gel route to explore the influence of Cr3+ substitution on their multifunctional properties. Rietveld refined PXRD patterns confirm the formation of a single-phase cubic spinel structure with crystallite sizes of ∼17-22 nm. The incorporation of Cr3+ ions, verified through HRTEM, FTIR, Raman, and XPS analyses, leads to lattice contraction due to the smaller ionic radius compared to Fe3+. Dielectric and impedance studies revealed Maxwell-Wagner interfacial polarization along with non-Debye type relaxation behavior, accompanied by a negative temperature coefficient of resistance. The frequency-dependent AC conductivity follows Jonscher's power law, indicating a thermally activated small polaron hopping conduction mechanism with activation energies in the range of 0.46-0.69 meV. Optical studies demonstrate a systematic increase in the band gap from 2.17 to 3.12 eV with increasing Cr3+ content, attributed to modification in M-O bonding. Magnetic measurements exhibit soft ferromagnetic behavior, with a reduction in saturation magnetization (54.74 to 29.53 emu g-1) and coercivity (998 to 317 Oe), primarily governed by weaker A-B super-exchange interactions and stronger spin canting. These properties indicate that the materials hold potential for capacitive and photocatalytic applications.

Based on previously reported high-accuracy electronic states of the ΛΣ presentation, we calculate the temperature-dependent photodissociation cross sections and rates of the NaS molecule in the ultraviolet region. The calculation includes transitions from the ground state X2Π to several excited electronic states, up to 12Δ. Particular attention is given to the nonadiabatic couplings between the 22Π-32Π and A2Σ+-22Σ+ states and their influence on the photodissociation dynamics. Spin-orbit coupling among the avoiding crossing electronic states and the ground state as well as the nonadiabatic couplings are incorporated through diabatic representation. Photodissociation cross sections obtained from the coupled channel calculations are compared with adiabatic results that include only spin-orbit coupling. The results show that nonadiabatic interactions significantly modify the cross sections near the avoided crossing regions and induce the pronounced Feshbach resonances. Using the local thermodynamic equilibrium cross sections, photodissociation rates of NaS are further evaluated under the standard interstellar radiation field and blackbody radiation fields. The rates show a relatively weak dependence on the molecular temperature. These results provide useful data for astrochemical modeling of NaS in ultraviolet radiation environments.

A 2-fold interpenetrated PtS-type spin-crossover (SCO) framework (1) was synthesized, exhibiting solvent-dependent stepwise spin transitions tuned by methanol/dichloromethane ratios. The coordination geometry distortion of secondary building units (SBUs) plays a key role in determining the interpenetration pattern and offers insight into the formation of the interpenetrated framework.

Iron dual-atom (Fe DA) nanozymes, structurally analogous to natural catalase, exhibit promising catalase-like (CAT-like) activity, yet further improving their catalytic performance and elucidating the underlying mechanism remain major challenges. Herein, we developed a cascade strategy integrating vacancy induction and electrostatic adsorption to construct two representative Fe DA nanozymes, pr-Fe-DA and py-Fe-DA, with coordination environments dominated by pyrrolic-N and pyridinic-N, respectively. The resulting py-Fe-DA exhibits an exceptionally high CAT-like activity of 100 U mg-1, which is 2.4 times that of pr-Fe-DA (42 U mg-1), representing the highest value reported to date. Mechanistic studies and density functional theory calculations reveal that modulating the nitrogen coordination environment from pyrrolic-N to pyridinic-N promotes an antiferromagnetic-to-ferromagnetic transition in the magnetic coupling between Fe sites. This transition enables spin-favorable H2O2 activation through parallel spin alignment of the oxygen atoms in adsorbed H2O2, thereby accelerating O─H bond cleavage and O2 generation while decreasing the Gibbs free energy change of the rate-determining step from 0.84 to 0.08 eV. Moreover, py-Fe-DA effectively alleviates oxidative stress and inflammation in rheumatoid arthritis models. These findings identify magnetic coupling as a key descriptor of CAT-like activity and establish magnetic-coupling engineering as a powerful strategy for designing high-performance nanozymes.

Perovskite transition metal oxide membranes with exact chemical composition and ordered lattice structures facilitate atomic-level catalytic mechanisms in diverse electrochemical processes, thus aiding in the development and design of potential catalysts. Nevertheless, the puzzling ascendancy of spin in the oxygen evolution reaction (OER) process remains an enigma owing to the robust correlation between TM 4d and oxygen 2p orbitals. Herein, we employed SrRuO3 (SRO) with 4d electron states as a ferromagnetic catalyst for the OER, which were deposited onto the flexible mica substrates. By applying compressive or tensile stresses to the SRO film, the bipolar enhancement of OER activity was observed. At the potential of 1.8 V, the current density (j) of SRO enhanced by ∼34% or ∼44%, with a 0.2% compressive or tensile strain, respectively, attributing to the diminished chemisorption of Ru-O. In addition, it was found that j enhanced by ∼86% or ∼104% and the overpotential reduced by ∼20% or ∼26% at a 0.2% compressive or tensile strain with a 13 kOe in-plane (IP) magnetic field, respectively. Those were attributing to the enhancement of the double exchange effect and the concentration of O22- in SRO, thus promoting electron transfer and regulating the adsorption/desorption capacity of reaction intermediates, respectively. Moreover, the magnetohydrodynamic-induced bubble effect is one of the factors that enhance the electrocatalytic activity. This investigation offers experimental evidence to comprehend the regulation of spin degree and electronic state during OER, hence advancing the design and engineering of the flexible magnetoelectrochemistry catalysts with encouraging prospects.

The development of structural concepts in polymers has repeatedly enabled advances in molecular organization and emergent functions. Here we introduce "bifacial ladder polymers" -rigid double-stranded backbones bearing two deliberately differentiated molecular faces- realized through a chirality-assisted synthetic strategy. To implement this architecture, we designed a C2-chiral 2,8-dibromoindenofluorene monomer bearing two different substituents with syn stereochemistry across the sp3-carbon pair, such that only one ladderization geometry is accessible. Polymerization of the enantiopure monomers with a diboronate comonomer under Suzuki-Miyaura conditions affords precursor polymers, which undergo regioselective ladderization to yield well-defined bifacial ladder polymers with fully preserved facial differentiation. The homochiral bifacial ladder polymers display emergent chiroptical behaviour in the solid state: thin films form one-handed supramolecular helices with circular dichroism intensities over 100-fold stronger than those of their monomeric or non-ladder analogues. Strikingly, these films also exhibit robust chirality-induced spin selectivity, with spin-polarization values exceeding ±90% and opposite signs for the two enantiomers, far surpassing their precursor polymers. These results demonstrate that bifacial ladder polymers provide a versatile platform for emergent self-assemblies and functions in organic polymeric materials.

Direct observation of 15N-13C heteronuclear correlations by conventional thermal NMR is limited by the low sensitivity of both nuclei. To overcome this limitation, we use low-field spin-lock-induced crossing signal amplification by reversible exchange (SLIC-SABRE) hyperpolarization to perform 15N-13C correlation spectroscopy in 15N-labeled small molecules containing 13C at natural abundance (1.1%). In SLIC-SABRE, polarization is transferred from parahydrogen to the substrate during their reversible interactions with an Ir-based complex. By tailoring the hyperpolarized spin order generated by SLIC-SABRE and the subsequent detection pathway, complementary one- and two-dimensional experiments with 15N and 13C detection provide site-specific connectivities, resolved 15N-13C J-couplings, and 13C-induced isotope shifts of the 15N resonances. The approach is demonstrated for a selenadiazole derivative and metronidazole, with two-dimensional 15N-13C correlation spectra acquired in approximately 40 min. Together, these results demonstrate the potential of SLIC-SABRE for rapid, site-resolved heteronuclear correlation spectroscopy.

Spectroelectrochemical nuclear magnetic resonance (NMR) experiments are faced with numerous challenges originating from shielding effects and susceptibility gradients in samples, leading to inhomogeneities in the static magnetic fields B 0 and the radio frequency (rf) fields B 1 . Moreover, magnetic feedback caused by eddy currents in conductors can obstruct precise measurements. Previous works have shown that these eddy-current-induced magnetic field distortions can be accurately predicted by finite element method (FEM) simulations. In this work, we present a workflow combining FEM predictions with quantum optimal control (QOC) to tailor custom NMR pulses that exploit specific magnetic field distortions for selective excitation of affected sample regions. The desired selectivity was achieved using pattern pulses optimized for either a particular B 1 or Larmor frequency ν 0 . Experimental validation was performed on a heterogeneous phantom consisting of two cavities filled with two spectroscopically distinguishable liquids, one between copper disks to mimic an electrochemical cell and one between polymer disks as a reference. An over 30-fold suppression of the reference resonance in between polymer compared to the resonance in between copper disks was achieved, demonstrating how QOC-tailored pulses can selectively address FEM-predicted B 1 distortions in the vicinity of electrical conductors to achieve spatial selectivity with simultaneous ν 0 robustness. It was also demonstrated how QOC-tailored pulses can selectively excite specific ν 0 despite B 0 distortions, which implies that difficulties with conventional solvent suppression techniques in electrochemical setups can be mitigated using the adjustable robustness of QOC-tailored pulses. The presented approach sets the stage for gradient-free, localized in operando NMR in electrochemistry and material sciences, with the prospect of surface selectivity down to the detection limit of the setup.