Low State Research Articles

Towards Functionalization of Extracellular Vesicle with Single-Walled Carbon Nanotubes for Long-Term Imaging

In the past years, nanotechnology has been increasingly applied in modern medicine owing to their advantages including high drug loading, increased drug stability, longer circulation time, EPR effect, and lower systemic toxicity compared to small molecular drugs. While most nanomaterials are fabricated synthetically, extracellular vesicles (EVs) present a special class as they are naturally produced by mammalian cells during inward budding of endosomes, which seems beneficial regarding stability, immunotolerance, capacity to cross natural barriers, and inherent targeting properties in vivo compared to synthetically prepared nanomaterials. Although EV-based cancer vaccines are currently tested in clinical phases I and II, a huge gap, preventing broad application of EVs, remains the lack of detailed information concerning the in vivo behavior of EVs. To understand the role of EVs and to optimize their application in future, long-term tracking of EVs is crucial.Single-walled carbon nanotubes (SWCNTs), tube-like, carbon-based nanomaterials with a diameter of around 1 nm and a length of around 100 nm, holding great promise as imaging probes for medical diagnostics owing to their optical properties in the short-wave infrared region. The fluorescent properties of SWCNTs are caused by excitons (bound electron-hole pairs) those energetically favorable dark states result naturally in a low photoluminescence yield. A way to circumvent this effect is oxygen-doping of SWCNT or introduction of sp3 defects which lead to lower energetic states which trap excitons and circumvent dark states. This results in a prolonged photoluminescence lifetime and an emission in the short-wave infrared (SWIR) window allowing imaging with deep optical penetration, reduced scattering, and low autofluorescence. In addition, SWCNTs possess a high photostability, low photobleaching, and negligible fluorescence blinking. The high photostability of SWCNTs in combination with an emission in the SWIR window as well as a size in the nanometer regime, mark SWCNTs as excellent imaging probes for in vivo tracking of extracellular vesicles.To achieve specific labeling of EVs with SWCNTs, we are using bioorthogonal chemistry. Metabolic engineering of cells is an elegant method to equip membrane proteins with bioorthogonal reactive groups. To this end, cells are treated with unnatural sugars which are metabolically incorporated into the glycan chain of proteins. Recently, it was revealed that EVs from metabolically engineered cells also carry unnatural sugars in their membrane proteins. We successfully isolated EVs from MCF-7 cells, which were treated with azide-bearing mannose. Using Cy5-DBCO, we could prove that azide groups present on EVs were able to react with the dye. EVs isolated from metabolically engineered HeLa cells seemed to possess a too low number of azide groups. Hence, EVs were modified successfully with DSPE-PEG-azide. Modification of EVs with Cy5-DBCO enabled in vitro imaging.We followed several strategies to introduce DBCO groups onto SWCNTs to link those to EVs. We were able to successfully functionalize SWCNTs with ssDNA carrying DBCO as an end-group as well as DPSE-PEG-DBCO. However, due to lack of specificity we embarked to use sp3 defects as reactive sites for modification of SWCNTs. Diazonium salt chemistry was used to introduce sp3 defects with a carboxylic acid group which allows further modification using a DBCO end-functionalized PEG linker.Ultimately, we will conjugate DBCO-modified SWCNTs with azid-bearing EVs to enable long-term tracking in vivo.

Towards a Mechanistic Understanding of Transition-Metal Dissolution Phenomenon in Lithium-Ion Batteries

Dissolution of transition metals (TMs) from the layered NMC-type cathodes (LiNixMnyCozO2) occurs during cycling of lithium-ion full cells and is known to accelerate their capacity fade. This is because the dissolved metals migrate to the graphite anode and deposit there, where they accelerate irreversible active-lithium loss to reductive side reactions. The dissolution is known to get aggravated by cycling the cells to a greater upper cut-off voltage (UCV), where larger amounts of metals are typically found to be accumulated at the anode after long term cycling. At higher UCV oxygen loss from the cathode lattice also gets accelerated causing changes in the layered crystal structure at the surface level to a rock-salt and spinel mixture which has a very high impedance for Li-ion transport. Several other phenomena get accelerated as well, such as proton generation, and solvent decomposition etc. However, a complete mechanistic understanding of the how these phenomena impact the TM dissolution is lacking. For example, it is unclear whether the dissolution can occur in the charged state when the metals are in the oxidized state despite the presence of large number of acidic species, especially since most of the dissolved metal species typically detected in the electrolyte are in lower oxidation state. In this study, this question was targeted by aging the full graphite//NMC cells via long potentiostatic holds at UCV with/without any discharge steps, and recording the dissolved metals deposited at the graphite after aging. It is shown that a much greater amounts are deposited at the anode when discharge steps are included. Atomic structural changes from TM dissolution at the cathode surface corresponding to the two aging protocols in the charged/discharged state will also be presented.This work was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the U.S. Department of Energy (DOE) through Cathode-Electrolyte Interphase (CEI) Consortium. Part of the measurements was performed at the Center for Nanophase Materials Sciences (CNMS), which is sponsored at Oak Ridge National Laboratory by the Scientific User Facilities Division, Office of Basic Energy Sciences.

Combined Multireference-Multiscale Approach to the Description of Photosynthetic Reaction Centers.

A first-principles description of the primary photochemical processes that drive photosynthesis and sustain life on our planet remains one of the grand challenges of modern science. Recent research established that explicit incorporation of protein electrostatics in excited-state calculations of photosynthetic pigments, achieved for example with quantum-mechanics/molecular-mechanics (QM/MM) approaches, is essential for a meaningful description of the properties and function of pigment-protein complexes. Although time-dependent density functional theory has been used productively so far in QM/MM approaches for the study of such systems, this methodology has limitations. Here we pursue for the first time a QM/MM description of the reaction center in the principal enzyme of oxygenic photosynthesis, Photosystem II, using multireference wave function theory for the high-level QM region. We identify best practices and establish guidelines regarding the rational choice of active space and appropriate state-averaging for the efficient and reliable use of complete active space self-consistent field (CASSCF) and the N-electron valence state perturbation theory (NEVPT2) in the prediction of low-lying excited states of chlorophyll and pheophytin pigments. Given that the Gouterman orbitals are inadequate as a minimal active space, we define specific minimal and extended active spaces for the NEVPT2 description of electronic states that fall within the Q and B bands. Subsequently, we apply our multireference-QM/MM protocol to the description of all pigments in the reaction center of Photosystem II. The calculations reproduce the electrochromic shifts induced by the protein matrix and the ordering of site energies consistent with the identity of the primary donor (ChlD1) and the experimentally known asymmetric and directional electron transfer. The optimized protocol sets the stage for future multireference treatments of multiple pigments, and hence for multireference studies of charge separation, while it is transferable to the study of any photoactive embedded tetrapyrrole system.

Singlet Oxygen Photophysics: From Liquid Solvents to Mammalian Cells.

Molecular oxygen, O2, has long provided a cornerstone for studies in chemistry, physics, and biology. Although the triplet ground state, O2(X3Σg-), has garnered much attention, the lowest excited electronic state, O2(a1Δg), commonly called singlet oxygen, has attracted appreciable interest, principally because of its unique chemical reactivity in systems ranging from the Earth's atmosphere to biological cells. Because O2(a1Δg) can be produced and deactivated in processes that involve light, the photophysics of O2(a1Δg) are equally important. Moreover, pathways for O2(a1Δg) deactivation that regenerate O2(X3Σg-), which address fundamental principles unto themselves, kinetically compete with the chemical reactions of O2(a1Δg) and, thus, have practical significance. Due to technological advances (e.g., lasers, optical detectors, microscopes), data acquired in the past ∼20 years have increased our understanding of O2(a1Δg) photophysics appreciably and facilitated both spatial and temporal control over the behavior of O2(a1Δg). One goal of this Review is to summarize recent developments that have broad ramifications, focusing on systems in which oxygen forms a contact complex with an organic molecule M (e.g., a liquid solvent). An important concept is the role played by the M+•O2-• charge-transfer state in both the formation and deactivation of O2(a1Δg).

The Photophysics and Photochemistry of Phenylalanine, Tyrosine, and Tryptophan: A CASSCF/CASPT2 Study.

Among all amino acids, the three aromatic systems including phenylalanine, tyrosine, and tryptophan are known to manifest UV light absorption at the higher wavelengths. Their fluorescent properties are important for protein detection and determination of the spatial structure. Based on ab initio quantum chemical calculations, the absorption spectra in the 0-12 eV UV range of these aromatic amino acids were interpreted, and the photochemistry of the lowest-lying excited states was studied. For that, molecular ground-state geometries were determined using both the coupled-cluster single and double (CCSD) and complete active space self-consistent field (CASSCF) methods. The vertical electronic transition energies, associated oscillator strengths, and electric dipole moments of the lowest excited states were computed at the CASPT2//CASSCF level. The decay mechanisms of the lowest-energy excited states were investigated by performing minimum energy path (MEPs) computations. The results showed that the CCSD and CASSCF computations yielded similar structures. The lowest-energy S1 state in phenylalanine and tyrosine, and S1 and S2 in tryptophan are mainly described by the π → π* excitation localized in the aromatic ring. Upon light absorption, the main photoresponse of the molecules is driven by the benzene, phenol, and indole chromophoric units.

Experimental evidence that activewear retail imagery elicits physiological, attentional and self-reported markers of body image threat in women

Online apparel retail imagery is a prominent threat to women’s body image, particularly segments such as activewear which emphasize the value of women’s bodies. In a within-subjects experiment, we exposed women (N = 128) to imagery randomly selected from activewear, casualwear and homewares websites and measured their gaze behavior, physiological arousal, as well as subjective emotional states and body image ratings. Exposure to activewear retail imagery elicited significantly lower body image ratings, a higher negative emotional state, and a lower positive emotional state compared to the other website imagery conditions. Physiological arousal was significantly higher for both apparel imagery conditions compared to the homewares imagery condition. Body biased gaze behavior was significantly higher for the activewear imagery condition compared to the casualwear imagery condition. Notably, body shame moderated the self-reported but not the physiological experimental effects, such that women with higher body shame experienced stronger adverse changes in their body image and emotional state ratings following activewear exposure. Correlations revealed that self-reported experimental responses to activewear imagery were strongly associated with self-objectification, appearance comparison, disordered eating and body image coping attitudes. Thus, exposure to popular apparel may play a role in maintaining maladaptive body image attitudes and behaviors in women.

Collective rovibronic dynamics of a diatomic gas coupled by cavity

We consider an ensemble of homonuclear diatomic molecules coupled to the two polarization directions of a Fabry-Pérot cavity via fully quantum simulations. Accompanied by analytical results, we identify a coupling mechanism mediated simultaneously by the two perpendicular polarizations, and inducing polaritonic relaxation towards molecular rotations. This mechanism is related to the concept of light-induced conical intersections (LICIs). However, unlike LICIs, these nonadiabatic pathways are of a collective nature, since they depend on the intermolecular orientation of all electronic transition dipoles in the polarization plane. Notably, this rotational mechanism directly couples the bright upper and lower polaritonic states, and it stays in direct competition with the collective relaxation towards dark states. Published by the American Physical Society 2024

Damage deformation properties and acoustic emission characteristics of hard-brittle rock under constant amplitude cyclic loading

In order to study the deformation and damage characteristics of the limestone specimens with high strength and brittleness under constant amplitude cyclic loading, the deformation and the acoustic emission (AE) characteristics were analysed, and the relationship between them was sought. The damage variables under different amplitude cyclic loading were defined by AE counts. The results showed that the radial deformation of the limestone specimens was more sensitive and unstable than the axial deformation. The concept of apparent residual strain was proposed to describe the specimen deformation characteristics, and it resulted that the radial apparent residual strain produced at higher stress state would recover at lower stress state. The limestone specimens showed obvious Kaiser effect and Felicity effect under cyclic loading. When the upper limit of the cyclic loading was close to the peak stress of the specimen, the AE counts generated in unloading sections were almost the same as that in the loading sections. The damage was increased as the amplitude and the stress level increased and the unloading process at higher stress level would also lead to the aggravation of damages. Specimens would absorb more energy under cyclic loading than under uniaxial loading. Reasonable driving parameters should be controlled in underground excavation practice, to ensure that the stress level of surrounding rock mass in a periodic stress state is located before peak stress and such that to limit the occurrence of rock burst to a certain extent.

Environmental impacts from traffic on highway construction work zones: Framework and simulations

Emissions from internal combustion engine vehicles on highways are the major contributors to global warming in the United States. Transportation sector pavement-related emissions come from gasolines and diesel use in vehicles from pavement-vehicle interaction, which is affected by pavement conditions, and by the trucking of new pavement materials and demolition. The objective of this study was to develop a framework for determining the fuel use resulting in environmental impacts caused by construction work zones (CWZs) on a range of vehicles and to produce initial calculations of these impacts by modeling traffic closure conditions for highway maintenance and rehabilitation activities. The study included two common highway categories—freeways/multi-lane highways and two-lane highways. The framework was demonstrated using three CWZ operations under different traffic congestion levels. In the simulation results for a freeway with a CWZ and heavy congestion, fuel consumption increased by 85% and the carbon-dioxide equivalent emissions increased by 86%. Changing CWZ traffic congestion from heavy (average speed 5 mph) to medium (average speed 25 mph for a freeway section) reduced fuel consumption by 40% on a freeway. This study also included use of a pilot car in a CWZ on a two-lane road typical of lower traffic volume state highways and county roads to compare with the drive cycles in MOVES used for the scenarios. The pilot-car operation scenario results indicate that a one-lane closure with pilot-car operation on a two-lane road might consume 13% excess fuel because of idling time and the slow movement of vehicles following the pilot car.

The Effects of Playing Versus Watching an Interactive Video Game Featuring an Older Adult Protagonist on State Empathy and Ageism Reduction.

This study tested how increased modality interactivity (e.g., playing vs. watching a game) can augment empathy and reduce ageism toward older adults among college-aged students. An experiment (n = 201) examined the effects of playing a video game that featured an older adult protagonist. Relative to those who spectated the game, participants who played the game had increased state empathy on subfactors, including shared affect, empathic motivation, and helping motivation. Moreover, shared affect mediated the link between playing a game featuring an older adult protagonist and ageism. Participants with higher trait empathy showed lower state empathy after playing, whereas participants with lower trait empathy displayed increased post-game state empathy. Overall, the results supported the modality interactivity model suggesting fruitful avenues for future research.

The dynamical evolution of exciton-polaritons in asymmetric ring-step potential well

The exciton-polariton, a quasi-particle formed by the coupling of excitons and photons, exhibits a semi-light-semi-matter nature, inheriting the advantages of both constituents and capable of achieving Bose-Einstein condensation at room temperature. This paper investigates the evolution of superposition states of semiconductor microcavity exciton-polariton Bose–Einstein condensate (BEC) within a ring-shaped structure. By employing theoretical modeling, the time-dependent dynamics of the superposition states of exciton-polaritons bound within a unique asymmetric ring-step potential well structure are analyzed, focusing on halide perovskite semiconductor materials. The study reveals correlations between the potential well structure of this step-like configuration and the transition of exciton-polariton BEC superposition states, shedding light on the evolution paths of BEC systems under specific structural influences and the fluctuation patterns of excitonic fields. These findings hold relevance for experimental manipulations of exciton-polariton superposition states within microcavities. This research demonstrates that ring-step potential well structures influence the excitation and evolution of exciton-polariton BEC superposition states, leading to transitions towards higher or lower order states. This transition is reflected macroscopically in alterations in the number and spatial distribution of interference petals in the superposition states. We consider initial states with orbital angular momentum quantum number l = 2, 3, 4, respectively. By exploiting the different structural relationships of ring-step potential wells, we achieve controlled evolutions of macroscopic occupation states, with interference petal numbers ranging from 4 to 6, 4–8, 6–8, 6–10, 8–10, 8–12, and 6–4.

Electrochemical properties of tungsten doped LiNi0.9Co0.1O2 lithium-ion battery cathode materials

High-nickel layered cathode materials for lithium-ion batteries have received widespread attention in new energy vehicles for their excellent specific energy and cost advantages, and are considered to be the most promising cathode materials for high-energy density lithium-ion batteries. Despite its many advantages, poor thermal stability and rapid capacity degradation have greatly limited its large-scale application. Ion doping is considered to be an effective way to improve its drawbacks, and in this paper, a series of W-doped LiNi0.9Co0.1O2 cathode materials were prepared using WO3 as a tungsten source. Among them, 1 mol% W doping was the most effective, and its reversible capacity of 204.44 mA g −1 still had 93.25 % capacity retention after 100 this cycles at 1C. Combined with DFT calculations, it is found that the introduction of W does not change the original layered structure and the material transitions from semi-metallic to metallic at lower doping concentrations, resulting in more electrons occupying the Fermi energy levels to enhance its electrical conductivity and leading to an elevated spin state and a lower oxidation state of Ni.

The coach bots are coming: exploring global coaches’ attitudes and responses to the threat of AI coaching

ABSTRACT Artificial intelligence (AI) in business coaching, as in other human resource development professional service roles, opens up the possibility of multiple chances, such as cost- and time-effective gains. However, as AI can act autonomously and may surpass human performance, it can both lead to unforeseen risks as well as create a threat for professional service workers, including business coaches. Using a within-subject threat manipulation design, the present research investigated whether business coaches (N = 436; from over 50 different countries) respond to the topic of AI in coaching with heightened threat-related affective states and how this change affects their attitude towards the topic. Expectedly, the topic evoked higher behavioral inhibition and lower behavioral activation threat-related affective states, leading to lower curiosity in and a more negative opinion of AI in coaching. Theoretical and practical implications are addressed to lower the coaches’ threat-related affective states towards AI application in professional services. A hybrid approach between responsible AI and an ethically skilled and professionally trained coach is recommended.

Influence of support properties on the activity of 2Cr-Fe/MgO-MO2 catalysts (M = Ce, Zr, CeZr and Si) for the dehydrogenation of n-octane with CO2

The influence of the support on catalytic activity and stability of supported 2Cr-Fe bimetallic catalysts for the CO2-assisted dehydrogenation (DH) of n-octane has been investigated. Four MgO modified supports viz; MgO-CeO2 (MgCe), MgO-ZrO2 (MgZr), MgO-CeO2-ZrO2 (MgCeZr) and MgO-SiO2 (MgSi) were synthesized by the sol-gel combustion technique. The supported catalysts were in turn prepared by vacuum impregnation and thereafter tested for the CO2-assisted DH of n-octane. The catalysts were characterized by inductively coupled plasma optical emission spectroscopy (ICP-OES), X-ray diffraction (XRD), N2-physisorption, Raman spectroscopy, transmission electron microscopy (TEM), electron dispersive x-ray (EDX), temperature programmed desorption of CO2 (CO2-TPD), temperature programmed reduction and oxidation (H2-TPR and CO2-TPO), electron paramagnetic resonance (EPR) and thermal gravimetric analysis (TGA) techniques. Raman results showed that the CrOx is stabilized as mono- and/or polynuclear Cr(VI) species over the 2Cr-Fe/MgCe catalyst, which are reduced to lower oxidation state species during the DH reaction. The 2Cr-Fe/MgZr, 2Cr-Fe/MgCeZr and 2Cr-Fe/MgSi catalysts stabilized the CrOx as polymerized species, forming the more active Cr-O-Fe polymer units on the catalysts’ surface. XRD, TEM and EDX results showed that the ZrO2-containing supports have smaller particles and stabilized the active metal oxides in a more dispersed amorphous state. The CO2-TPO of the pre-reduced catalysts and EPR of the used catalysts indicated that the 2Cr-Fe/MgCeZr undergoes significant re-oxidation by CO2 during the catalytic process. The 2Cr-Fe/MgCe was the least active, while the 2Cr-Fe/MgZr catalyst showed the best performance and stability over three regeneration cycles. Selectivity to C8 products (octenes and aromatics) was found to strongly depend on the surface basicity of the catalysts. Deactivation of the catalysts was found to follow first order kinetics and coke deposition was identified as the major cause.

Long-Range Configuration Interaction with an Ab Initio Short-Range Correction and an Asymptotic Lower Bound†.

Short-range corrections to long-range selected configuration interaction calculations are derived from perturbation theory considerations and applied to harmonium (with two to six electrons for some low-lying states). No fitting to reference data is used, and the method is applicable to ground and excited states. The formulas derived are rigorous when the physical interaction is approached. In this regime, the second-order expression provides a lower bound to the long-range full configuration interaction energy. A long-range/short-range separation of the interaction between electrons at a distance of the order of one atomic unit provides total energies within chemical accuracy, and, for the systems studied, provide better results than short-range density functional approximations.

The weakly bound states in Gaussian wells: From the binding energy of deuteron to the electronic structure of quantum dots

AbstractGaussian potentials serve as a valuable tool for the comprehensive modeling of short‐range interactions, spanning applications from Nuclear Physics to the artificial confinement of electrons within quantum dots. This study focuses on examining the lowest states within Gaussian wells, with particular emphasis on the weakly bound regime. The analysis delves into the asymptotic behavior of the exact wave function at both small and large distances, motivating the development of a few parametric Ansatz which is locally accurate and yields to a fast convergent basis set. To validate its efficacy, we assess its convergence rate using a toy model of Nuclear Physics, specifically for Deuteron. Furthermore, we employ the expansion of the energy close to the threshold to derive an analytical formula for the binding energy of the Deuteron whose accuracy improves as the effective parameter approaches the critical. To conclude our study, we test the ability of our Ansatz to describe relativistic corrections into a quantum dot and its performance as an orbital in the exploration of the electronic structure of a two‐electron quantum dot.

Electronic Structure Methods for Simulating Flavin's Spectroscopy and Photophysics: Comparison of Multi-reference, TD-DFT, and Single-Reference Wave Function Methods.

The use of flavins and flavoproteins in photocatalytic, sensing, and biotechnological applications has led to a growing interest in computationally modeling the excited-state electronic structure and photophysics of flavin. However, there is limited consensus regarding which computational methods are appropriate for modeling flavin's photophysics. We compare the energies of low-lying excited states of flavin computed with time-dependent density functional theory (TD-DFT), equation-of-motion coupled cluster (EOM-EE-CCSD), scaled opposite-spin configuration interaction [SOS-CIS(D)], multiconfiguration pair-density functional theory (MC-PDFT), and several multireference perturbation theory (MR-PT2) methods. In the first part, we focus on excitation energies of the first singlet excited state (S1) of five different redox and protonation states of flavin, with the goal of finding a suitable active space for MR-PT2 calculations. In the second part, we construct two sets of one-dimensional potential energy surfaces connecting the S0 and S1 equilibrium geometries (S0-S1 path) and the S1 (π,π*) and S2 (n,π*) equilibrium geometries (S1-S2 path). The first path therefore follows a Franck-Condon active mode of flavin while the second path maps crossings points between low-lying singlet and triplet states in flavin. We discuss the similarities and differences in the TD-DFT, EOM-EE-CCSD, SOS-CIS(D), MC-PDFT and MR-PT2 energy profiles along these paths. We find that (TD-)DFT methods are suitable for applications such as simulating the spectra of flavins but are inconsistent with several other methods when used for some geometry optimizations and when describing the energetics of dark (n,π*) states. MR-PT2 methods show promise for the simulation of flavin's low-lying excited states, but the selection of orbitals for the active space and the number of roots used for state averaging must be done carefully to avoid artifacts. Some properties, such as the intersystem crossing geometry and energy between the S1 (π,π*) and T2 (n,π*) states, may require additional benchmarking before they can be determined quantitatively.

A Multipronged Bioengineering, Spectroscopic and Theoretical Approach in Unravelling the Excited-State Dynamics of the Archetype Mycosporine Amino Acid.

Mycosporine glycine (MyG) was produced by the fermentation of a purposely engineered bacterial strain and isolated from this sustainable source. The ultrafast spectroscopy of MyG was then investigated in its native, zwitterionic form (MyGzwitter), via femtosecond transient electronic absorption spectroscopy. Complementary nonadiabatic (NAD) simulations suggest that, upon photoexcitation to the lowest excited singlet state (S1), MyGzwitter undergoes efficient nonradiative decay to repopulate the electronic ground state (S0). We propose an initial ultrafast ring-twisting mechanism toward an S1/S0 conical intersection, followed by internal conversion to S0 and subsequent vibrational cooling. This study illuminates the workings of the archetype mycosporine, providing photoprotection, in the UV-B range, to organisms such as corals, macroalgae, and cyanobacteria. This study also contributes to our growing understanding of the photoprotection mechanisms of life.

Dual-Confinement and Surface-Ionization Induced Controllable Regulate Visible-Light-Activated Colorful Afterglow of Carbon Dots for Multifunctional Applications.

Low-energy visible-light-activated carbon dots (CDs)-based afterglow materials are difficult to realize due to the inherent aromatic carbon with high-energy absorption and the lack of effective regulation. Here, a new strategy for visible-light-activated CDs is proposed by combining dual-confinement and surface-ionization, which employs NaOH for additional confinement and surface ionization of CDs in a single boric acid (BA) matrix. The comparison experiments show that: i) shifting the excitation from UV-light to vis-light is realized by enhancing the low-energy surface states n→π* transition of the CDs by surface ionization of NaOH. ii) CDs are additionally protected by a more stable Na─O ionic bond after NaOH confinement, resulting in a brighter afterglow. iii) the energy gap (ΔEST) between the lowest singlet and triplet states is gradually shortened as increasing NaOH content, facilitating intersystem crossing, prolonging the lifetime of triplet excitons and efficiency. Further, vis-light-excited colorful afterglow powders are fabricated based on Förster Resonant Energy Transfer by combining the fluorescent dye 5-carboxytetramethylrhodamine. Finally, advanced white-light-activated time-resolved anti-counterfeiting and intelligent traffic flashing signs are realized. The work may shed new light on the design of low-energy-activated afterglow materials and broaden the application scenarios in the daily lives of human society.

Theoretical investigation of the electronic structure of the Rhodium Halides molecules RhF and RhCl with dipole moment calculation

The current study involves an ab initio exploration of the ground and low-lying excited electronic states of the rhodium halide molecules RhF and RhCl using the complete active space self-consistent field (CASSCF) with multireference configuration interaction (MRCI+Q) method including single and double excitations and with Davidson corrections. We investigated the potential energy curves, the transition and permanent electric dipole moments, the electronic energy relative to the ground state Te, the harmonic frequency ωe, the internuclear distance Re, and the rotational constant Be corresponding to each of the bounded states. Our findings demonstrate good agreement with the available experimental data. Notably, this work represents the inaugural theoretical investigation of the excited states of RhF and RhCl molecules, identifying the ground state of both to be X3Π, as observed in the sole two experimental investigations.