The 100 most-cited articles in Physical Chemistry Chemical Physics, 2022

Specific ion effects (SIE), encompassing the Hofmeister Series, have been known for more than 130 years since Hofmeister and Lewith's foundational work. SIEs are ubiquitous and are observed across the medical, biological, chemical and industrial sciences. Nevertheless, no general predictive theory has yet been able to explain ion specificity across these fields; it remains impossible to predict when, how, and to what magnitude, a SIE will be observed. In part, this is due to the complexity of real systems in which ions, counterions, solvents and cosolutes all play varying roles, which give rise to anomalies and reversals in anticipated SIEs. Herein we review the historical explanations for SIE in water and the key ion properties that have been attributed to them. Systems where the Hofmeister series is perturbed or reversed are explored, as is the behaviour of ions at the liquid-vapour interface. We discuss SIEs in mixed electrolytes, nonaqueous solvents, and in highly concentrated electrolyte solutions - exciting frontiers in this field with particular relevance to biological and…

Predicting lithium-ion battery degradation is worth billions to the global automotive, aviation and energy storage industries, to improve performance and safety and reduce warranty liabilities. However, very few published models of battery degradation explicitly consider the interactions between more than two degradation mechanisms, and none do so within a single electrode. In this paper, the first published attempt to directly couple more than two degradation mechanisms in the negative electrode is reported. The results are used to map different pathways through the complicated path dependent and non-linear degradation space. Four degradation mechanisms are coupled in PyBaMM, an open source modelling environment uniquely developed to allow new physics to be implemented and explored quickly and easily. Crucially it is possible to see 'inside the model and observe the consequences of the different patterns of degradation, such as loss of lithium inventory and loss of active material. For the same cell, five different pathways that can result in end-of-life have already been found,…

In this paper, the history, present status, and future of density-functional theory (DFT) is informally reviewed and discussed by 70 workers in the field, including molecular scientists, materials scientists, method developers and practitioners. The format of the paper is that of a roundtable discussion, in which the participants express and exchange views on DFT in the form of 302 individual contributions, formulated as responses to a preset list of 26 questions. Supported by a bibliography of 777 entries, the paper represents a broad snapshot of DFT, anno 2022.

We present a novel, structurally simple, multifunctional broadband absorber. It consists of a patterned vanadium dioxide film and a metal plate spaced by a dielectric layer. Temperature control allows flexible adjustment of the absorption intensity from 0 to 0.999. The modulation mechanism of the absorber stems from the thermogenic phase change properties of the vanadium dioxide material. The absorber achieves total reflection properties in the terahertz band when the vanadium dioxide is in the insulated state. When the vanadium dioxide is in its metallic state, the absorber achieves near-perfect absorption in the ultra-broadband range of 3.7 THz-9.7 THz. Impedance matching theory and the analysis of electric field are also used to illustrate the mechanism of operation. Compared to previous reports, our structure utilizes just a single cell structure (3 layers only), and it is easy to process and manufacture. The absorption rate and operating bandwidth of the absorber are also optimised. In addition, the absorber is not only insensitive to polarization, but also very tolerant to the…

film phase transition process. The impedance matching theory is applied to explain the high level of absorption generated by the absorber. Finally, the effects of the structural parameters on the performance of the absorber are analysed. This work will have many applications in the terahertz field and offers a wide range of ideas for the design of terahertz-enabled devices.

and 18.97%, respectively. Moreover, the effect of different illumination angles on the optical absorption of the SCs was explored. The SCs have good absorption when the incident angles are in the range from 0 degrees to 60 degrees. Furthermore, the underlying mechanism for the enhancement of photon absorption in the SCs was discussed through careful analysis of the electric field intensity profile at different wavelengths. It was found that the electric field tends to concentrate around the bottom pyramids and top trapezoidal pyramids even for the long-wave band, which results in an excellent light-trapping performance.

Deep eutectic solvents (DESs) are emerging as novel green solvents for the processes of mass transport and heat transfer, in which the viscosity of DESs is important for their industrial applications. However, for DESs, the measurement of viscosity is time-consuming, and there are many factors influencing the viscosity, which impedes their wider application. This study aims to develop a data-driven model which could accurately and rapidly predict the viscosity of diverse DESs at different temperatures, and furthermore boost the design and screening of novel DESs. In this work, we collected 107 DESs with 994 experimental values of viscosity from published works. Given the significant effect of water on viscosity, the water content of each collected DES was labeled. The Morgan fingerprint was first employed as a feature to describe the chemical environment of DESs. And four machine learning algorithms were used to train models: support vector regression (SVR), random forest (RF), neural network (NN), and extreme gradient boosting (XGBoost), and XGBoost showed the best predictive…

from Fe 2p/O 1s intensity ratios. Similar considerations about the importance of many-body effects are likely to be relevant for other ionic compounds as well.

, respectively. By establishing and demodulating a sensing matrix, the sensor can not only measure the temperature and magnetic field simultaneously but also solve the temperature cross-sensitivity problem. In addition, when the temperature exceeds a certain value, the proposed sensor is expected to achieve dual-parameter sensing without a matrix. The proposed dual-parameter SPR-PCF sensor has a unique structure and excellent sensing performance, which are important for the simultaneous sensing of multiple basic physical parameters.

carbon allows these novel materials to be tailored with additional functionalities with the purpose of tuning intrinsic properties. There has been a vivid discussion on the non-covalent modification of GO; however, a comprehensive summary of the chemical functionalization which enables forming a stable particle is still elusive. Hence, in this study, we summarize recently advanced methodologies used for designing the functional GO for their use in specific applications. Together with a brief discussion on the essential characterization techniques, this study will provide fundamental insight into the latest developments in the preparation of covalently modified GO derivatives, thereby leading to their broader utilization in future.

is transited from the isolating state to the conducting state, the metamaterial does not only exhibit a linear dichroism response but also perform linear-to-linear and linear-to-circular polarization conversions simultaneously. Specifically, the designed device behaves like a half-wave plate, where a linear polarization conversion ratio exceeds 96.5% at a frequency of 9.17 THz. Meanwhile, it acts as a quarter-wave plate which can convert the linear polarization light into left-handed and right-handed circularly polarized lights with high efficiencies at frequencies of 9.04 and 9.3 THz, respectively. Moreover, the performance of the designed structure can be actively controlled by adjusting the geometrical parameters and Fermi energy of graphene. This work provides a new avenue in developing multi-functional terahertz metamaterial devices.

Rotational spectroscopy is the technique of choice for investigating molecular structures in the gas phase. Indeed, rotational constants are strongly connected to the geometry of the molecular system under consideration. Therefore, they are powerful tools for assessing the accuracy that quantum chemical approaches can reach in structural determinations. In this review article, it is shown how it is possible to measure the accuracy of a computed equilibrium geometry based on the comparison of rotational constants. But, it is also addressed what accuracy is required by computations for providing molecular structures and thus rotational constants that are useful to experiment. Quantum chemical methodologies for obtaining the "0.1% accuracy" for rotational constants are reviewed for systems ranging in size from small molecules to small polycyclic aromatic hydrocarbons. This accuracy for systems containing two dozen or so atoms opens the way towards future applications such as the accurate characterization of non-covalent interactions, which play a key role in several biological and…

, a MO/RhB/MB mixed solution) at different pH values and containing different inorganic anions. Based on the experimental data and density functional theory (DFT) calculations, the involved photocatalytic mechanism was discussed.

Deep eutectic solvents (DESs) have emerged as a new class of green, designer and biocompatible solvents, an alternative to conventional organic solvents and ionic liquids (ILs) which are comparatively toxic and non-biodegradable. DESs are eutectic mixtures that are formed when a hydrogen bond acceptor (HBA) is mixed with a hydrogen bond donor (HBD) at particular molar ratios by mechanical grinding or under mild heating conditions. Very recently, these solvents have been the center of attention for researchers in biotechnology, biomedicine and various scientific applications. These environmentally benign solvents have a close analogy with ILs; however, they offer certain unique merits over traditional ILs. DESs display remarkable properties such as easy preparation, tunable composition, biodegradability, recyclability, inherently low toxicity, sustainability and biocompatibility; these special features validate DESs as new potential solvents/co-solvents for biomolecules. Mechanistically, the biocompatibility and protein friendly nature of DESs depend on various factors, which include…

searching the transition state (TS) and performing intrinsic reaction coordinate (IRC) simulations, we further checked the ESIPT mechanism. Through gaining insights in spectral variations in solvents, we uncovered the solvent-polarity-dependent spectral behaviors. We sincerely hope this work will not only help clarify the solvent-polarity-regulated dynamical behaviors of BI3HC but also pave the way for further explorations and applications of other 3-hydroxychromone derivatives.

= 0.171) which is characterized by a melting point of 244 K. This temperature is only 16 K below the melting point of neat EG. Thus, neither from its particular composition nor from the observed melting-point depression of {ChCl + EG} mixtures can ethaline be considered a "deep eutectic solvent". Surprisingly, despite ChCl being an electrolyte dissolved in EG, the phase diagram is that of an ideal binary mixture.

Considering their remarkable chemical stability, the precursors of cyclo[18]carbon (C18), C18-(CO)n (n = 2, 4, and 6), have more practical significance than the elusive C18 ring. In the present paper, the electronic spectrum and (hyper)polarizability of the C18-(CO)n (n = 2, 4, and 6) are studied by theoretical calculations and analyses for revealing the utility of introduction of carbonyl (-CO) groups on molecular optical properties. The analysis results show that the successive introduction of -CO groups leads to red-shift of the absorption spectrum, but maximum absorption of all molecules is mainly due to the charge redistribution caused by electron transition within C18 ring. Except for the vanishing first hyperpolarizability of C18-(CO)6 results from its octupolar character, the (hyper)polarizabilities of the precursors present an ascending trend with the increase of -CO groups in the molecule, and the higher-order response properties are more sensitive to the number of -CO groups. By means of (hyper)polarizability density analysis and (hyper)polarizability contribution…

insulating layer, and a TiN ring array. In the spectral range of 300-2500 nm, an average absorption of 97.6% is achieved. The percentage of absorbed energy in the AM1.5 spectral radiation can reach 95.8%. The electric and magnetic field distributions show that the high absorption is attributed to the coupling effect of surface plasmon resonance, guided mode resonance and cavity resonance. Furthermore, the absorber is found to maintain high absorption performance at large angles of solar radiation and to be insensitive to polarization. The designed absorber maintains its broadband absorption performance well within certain geometric tolerances. This reduces the complexity and cost of manufacturing and facilitates practical applications. The research indicates that this work will benefit the design and application of solar thermal conversion and thermophotovoltaic systems.

surface complexation reactions followed by ligand exchange for chloride in the bulk solvent. Interestingly, the safety and degradability of DESs reported in the literature are superior to those of inorganic acids. Both DESs and inorganic acids have excellent metal leaching efficiencies (>99%). However, the reaction kinetics of DESs are 2-3 orders of magnitude slower than those of inorganic acids. A significant advantage of DESs is that they can be regenerated and recycled multiple times after recovering metals by electrochemical deposition or precipitation. In the future, the development of efficient and selective DESs still requires a lot of attention.

< 1). The FBM-SBM process is aging in a manner similar to SBM. The velocity autocorrelation function (ACF) of particle increments of FBM-SBM exhibits a dip when the parent FBM process is subdiffusive. Both for sub- and superdiffusive FBM contributions to the FBM-SBM process, the SBM exponent affects the long-time decay exponent of the ACF. Applications of the FBM-SBM-amalgamated process to the analysis of SPT data are discussed. A comparative tabulated overview of recent experimental (mainly SPT) and computational datasets amenable for interpretation in terms of FBM-, SBM-, and FBM-SBM-like models of diffusion culminates the presentation. The statistical aspects of the dynamics of a wide range of biological systems is compared in the table, from nanosized beads in living cells, to chromosomal loci, to water diffusion in the brain, and, finally, to patterns of animal movements.

detecting photons or electrons, making them applicable to different chiral phases, from gases to liquids to amorphous solids. The electric-dipole revolution has also enabled enantio-sensitive manipulation of chiral molecules with light. This manipulation includes exciting and controlling ultrafast helical currents in vibronic states of chiral molecules, enantio-sensitive control of populations in electronic, vibronic and rotational molecular states, and opens the way to efficient enantio-separation and enantio-sensitive trapping of chiral molecules. The word "perspective" has two meanings: an "outlook" and a "point of view". In this perspective article, we have tried to cover both meanings.

density functional theory calculations. The phonon dispersion, molecular dynamics simulation, and cohesive energy mechanical properties of the penta-PdPSe are verified to confirm its stability. The phonon spectrum represents a striking gap between the high-frequency and the low-frequency optical branches and an out-of-plane flexure mode with a quadratic dispersion in the long-wavelength limit. The Poisson's ratio indicates that penta-PdPSe is a brittle nanosheet. The penta-PdPSe is a semiconductor with an indirect bandgap of 1.40 (2.07) eV using the PBE functional (HSE06 hybrid functional). Optical properties simulation suggests that PdPSe is capable of absorbing a substantial range of visible to ultraviolet light. Band alignment analysis also reveals the compatibility of PdPSe for water splitting photocatalysis application. By combining the electrical and thermal transport properties of PdPSe, we show that a high power factor is achievable at room temperature, thus making PdPSe a candidate material for thermoelectric applications. Our findings reveal the strong potential of…

The growth of single hydrogen bubbles at micro-electrodes is studied in an acidic electrolyte over a wide range of concentrations and cathodic potentials. New bubble growth regimes have been identified which differ in terms of whether the bubble evolution proceeds in the presence of a monotonic or oscillatory variation in the electric current and a carpet of microbubbles underneath the bubble. Key features such as the growth law of the bubble radius, the dynamics of the microbubble carpet, the onset time of the oscillations and the oscillation frequencies have been characterized as a function of the concentration and electric potential. Furthermore, the system's response to jumps in the cathodic potential has been studied. Based on the analysis of the forces involved and their scaling with the concentration, potential and electric current, a sound hypothesis is formulated regarding the mechanisms underlying the micro-bubble carpet and oscillations.

DFT calculations of reaction mechanisms in solution have always been a hot topic, especially for transition-metal-catalyzed reactions. The calculation of solvation energy is performed using either the polarizable continuum model (PCM) or the universal solvation model SMD. The PCM calculation is very sensitive to the choice of atomic radii to form a cavity, where the self-consistent isodensity PCM (SCI-PCM) has been recognized as the best choice and our IDSCRF radii can provide a similar cavity. Moving from a gas-phase case to a solution case, dispersion energy and entropy should be carefully treated. The solvent-solute dispersion is also important in solution systems, and it should be calculated together with the solute dispersion. Only half of the solvent-solute dispersion energy from the PCM calculation belongs to the solute molecules to maintain a thermal equilibrium between a solute molecule and its cavity, similar to the treatment of electrostatic energy. Relative solute dispersion energy should also be shared equally with the newly formed cavity. The entropy change from a gas…

), morphological tuning, through various solution-assisted synthesis processes, including liquid-phase exfoliation, heat-up, hot-injection methods, hydrothermal/solvothermal routes and template-mediated synthesis processes. In this review we will discuss recent developments in transition metal chalcogenides (TMCs), the role of TMCs for hydrogen production and various strategies for surface functionalization to increase their activity, different synthesis methods, and prospects of TMCs for hydrogen evolution. We have included a brief discussion on the effect of surface hydrogen binding energy and Gibbs free energy change for HER in electrocatalytic hydrogen evolution.

The unique electronic and optical properties of Sb 2 S 3 and Sb 2 Se 3 are connected to their underlying crystal structures and chemical bonding.

). These superior properties, combined with its carbon abundance and light mass, make the biphenylene monolayer a promising high-performance anode for sodium-ion batteries (SIBs).

characterization techniques for the real-time observation of lithium dendrite growth are presented. To address the application issues, various potential research routes for improving the performance of LMBs are provided as well.

/SeMoS HSs, respectively. This work paves the way for designing highly efficient overall water-splitting photocatalysts using 2D materials.

(∼16%) and β-PtSSe (∼18%) makes them promising candidates for solar water splitting applications.

In admolecules, on graphene. This work provides knowledge for understanding the nucleation and intercalation mechanisms at the atomic scale and for carrying out epitaxial growth of 2D materials and graphene heterostructures.

) of the peripheral substitutions with respect to the α-cyano unit, and (iv) branching effect. In addition, we explain the utility of their unique AIE characteristics for various optoelectronic applications, including self-assembled nanostructures, chemical sensing, organogelation, white light emission, molecular switches, multiphoton absorption, liquid crystals, anion receptors, and biological probes. It is anticipated that organic materials with a cyanostilbene framework will continue to garner attention in the interdisciplinary fields of biology, chemistry, and materials science for diverse applications.

Covalent functionalization of the surface is more crucial in 2D materials than in conventional bulk materials because of their atomic thinness, large surface-to-volume ratio, and uniform surface chemical potential. Because 2D materials are composed of two surfaces with no dangling bond, covalent functionalization enables us to improve or precisely modify the electrical, mechanical, and chemical properties. In this review, we summarize the covalent functionalization methods and related changes in properties. First, we discuss possible sites for functionalization. Consequently, functionalization techniques are introduced, followed by the direct synthesis of functionalized 2D materials and characterization methods of functionalized 2D materials. Finally, we suggest how the issues may be solved to enlarge the research area and understanding of the chemistry of 2D materials. This review will help in understanding the functionalization of 2D materials.

Salinity energy generation (SEG) studies have only been done under isothermal conditions at ambient temperature. The production of salinity energy can be improved under non-isothermal conditions, albeit preserving the energy efficiency. In the current study, the effects of gradients of temperature and concentration on the salinity energy generation process were examined simultaneously. Based on the temperature-dependent properties resulting from both temperature and concentration gradients, a numerical study was carried out to determine the maximum efficiency of salinity energy generation in funnel-shaped soft nanochannels. It was presumed that a dense layer of negative charge, called a polyelectrolyte layer (PEL), is coated on the walls of the nanochannels. Co-current and counter-current modes were used to obtain temperature and concentration gradients. Under steady-state conditions, the Poisson-Nernst-Planck, Stokes-Brinkman, and energy equations were numerically solved using equivalent approaches. The results revealed that by increasing the temperature and concentration ratios in…

(from F to I). We obtain 14 optimal and unreported materials with suitable band gaps as potential alternative materials for Pb-based photovoltaic absorbers in PSCs. This theoretical investigation can provide theoretical guidance for developing novel lead-free PSC materials.

intracellular ROS generation without any light exposure. The designed nanoparticle can be used for the formulation of advanced antibacterial and antimicrobial materials and other cell therapy applications.

, can be changed individually in the simulations, so their effects can be directly observed. We evaluate the resulting EIS spectra by comparing two commonly used equivalent circuits with series and parallel connections respectively, which result in two signals with significantly different time constants. Both circuits can fit the EIS spectra and by extracting the values of the elements of one of the circuits, the values of the elements of the other circuit can be unequivocally obtained. Consequently, both can be used to analyse the EIS of a PSC. However, the physical meaning of each element in each circuit could differ. EIS can produce a broad range of physical information. We analyse the physical interpretation of the elements of each circuit and how to correlate the elements of one circuit with the elements of the other in order to have a direct picture of the physical processes occurring in the device.

and the formation of a guanine quartet as examples. The fact that a bond is always defined by the bound molecule, the fragments, and their states is universal and deeply physical, as we show here again for various examples. The results of the EDA-NOCV method are in full accordance with the physical mechanism of the chemical bond as revealed by Ruedenberg.

levels show that the singlet-triplet gap is inverted as compared to the one expected from Hund's rule, whereas all density functionals yield the triplet state as the lowest excited state. Double excitations responsible for the inverted singlet-triplet gap have been identified. Employing the spin-flip and ΔSCF methods, singlet-triplet inversion was obtained at the density functional theory level for some of the studied molecules.

and TM/GD systems, which will help understand the basic adsorption mechanism for practical hydrogen storage.

In this review, we discuss the recent progress in developing geminal-based theories for challenging problems in quantum chemistry. Specifically, we focus on the antisymmetrized geminal power, generalized valence bond, antisymmetrized product of strongly orthogonal geminals, singlet-type orthogonal geminals, the antisymmetric product of 1-reference orbital geminal, also known as the pair coupled cluster doubles ansatz, and geminals constructed from Richardson-Gaudin states. Furthermore, we review various corrections to account for the missing dynamical correlation effects in geminal models and possible extensions to target electronically excited states and open-shell species. Finally, we discuss some numerical examples and present-day challenges for geminal-based models, including a quantitative and qualitative analysis of wave functions, and software availability.

families as representatives, in sharp contrast to the enormously diverse variety of the traditional apolar nematic liquid crystals. Here, we report a design of novel ferroelectric nematic materials with highly fluorinated and rigid mesogens. Noteworthily, they show distinct chemical structural features compared with previous aromatic ester-based molecules. The ferroelectric nematic phase was identified and confirmed through rigorous experiments. The bulk polarization was found to become purely along the long axis director, creating giant dielectric anisotropy. This work demonstrates a great potential for expanding ferroelectric nematic material diversity and will accelerate the corresponding application research and technology innovation.

Dilution of a highly concentrated Li-salt/sulfolane electrolyte with a non-coordinating hydrofluoroether (HFE) solvent increases ionic conductivity and diffusivity but decreases the Li + transference number.

S or Se site, and better sensitivity with recycling potential could enable sensing application of the Janus MoSSe monolayer for toxic gases detection.

Efficient transport of both ionic and electronic charges in conjugated polymers (CPs) has enabled a wide range of novel electrochemical devices spanning applications from energy storage to bioelectronic devices. In this Perspective, we provide an overview of the fundamental physical processes which underlie the operation of mixed conducting polymer (MCP) devices. While charge injection and transport have been studied extensively in both ionic and electronic conductors, translating these principles to mixed conducting systems proves challenging due to the complex relationships among the individual materials properties. We break down the process of electrochemical (de)doping, the basic feature exploited in mixed conducting devices, into its key steps, highlighting recent advances in the study of these physical processes in the context of MCPs. Furthermore, we identify remaining challenges in further extending fundamental understanding of MCP-based device operation. Ultimately, a deeper understanding of the elementary processes governing operation in MCPs will drive the advancement in…

solar or forward osmosis, (4) the antifouling characteristics of hydrogels, and (5) melting point suppression and boiling point elevation, and solubility of salts in hydrogels. These properties are of interest in solar-driven interfacial water evaporation for desalination and wastewater treatment, atmospheric water harvesting, and forward osmosis. The reformulated thermodynamic framework will also be useful for understanding polymer electrolytes and ion transport in electrochemical and biological systems.

The Non-Covalent Interactions Atlas (https://www.nciatlas.org) has been extended with two data sets of benchmark interaction energies in complexes dominated by London dispersion. The D1200 data set of equilibrium geometries provides a thorough sampling of an extended chemical space, while the D442×10 set features dissociation curves for selected complexes. In total, they provide 5178 new CCSD(T)/CBS data points of the highest quality. The new data have been combined with previous NCIA data sets in a comprehensive test of dispersion-corrected DFT methods, identifying the ones that achieve high accuracy in all types of non-covalent interactions in a broad chemical space. Additional tests of dispersion-corrected MP2 and semiempirical QM methods are also reported.

molecular dynamics (AIMD) simulation by more than 3 orders of magnitude while preserving the accuracy of density functional theory (DFT) calculations. This enabled us to perform longer-time simulations at more realistic temperatures that traditional AIMD methods cannot achieve. With the advantage of the NNP in its powerful fitting ability and transferability, the NNP-based MD simulation can be widely applied to energetic material systems.

The SH250×10 dataset presented here extends the Non-Covalent Interactions Atlas database (https://www.nciatlas.org) to complexes bound by σ-hole interactions - halogen, chalcogen and pnictogen bonds. It comprises 250 complexes where Cl, Br, I, S, Se, P and As interact with diverse electron donors. An accurate CCSD(T)/CBS benchmark is provided for ten points along a dissociation curve of each complex. The SH250×10 set is used in testing a wide variety of DFT functionals and semiempirical quantum-mechanical methods. In DFT calculations, the new data set exposes large errors of some functionals related to exaggerated charge transfer. The size and diversity of the data set have also been exploited in the reparametrization of a halogen-bond correction for the PM6 semiempirical method.

Monolayers GdX 2 (X = F, Cl, and Br) are predicted to be a class of intriguing 2D intrinsic ferrovalley semiconductors with potential applications in nanoscale spintronics and valleytronics.

Aromaticity is a fundamental concept in chemistry, underpinning the properties and reactivity of many organic compounds and materials. The ability to easily and accurately discern aromatic behavior is key to leveraging it as a design element, yet most aromaticity metrics struggle to combine accurate quantitative evaluation, intuitive interpretability, and user-friendliness. We introduce a new method, NICS2BC, which uses simple and inexpensive NICS calculations to generate information-rich and easily-interpreted bond-current graphs. We test the quantitative and qualitative characterizations afforded by NICS2BC for a selection of molecules of varying structural and electronic complexity, to demonstrate its accuracy and ease of analysis. Moreover, we show that NICS2BC successfully identifies ring-current patterns in molecules known to be difficult cases to interpret with NICS and enables deeper understanding of local aromaticity trends, demonstrating that our method adds additional insight.

RR electrocatalysts. DFT calculations are performed to confirm the surface catalytic sites, evaluate the catalytic activity, reveal the possible reaction mechanisms, and design novel structures with high catalytic performance. By discussing the currently applied computational methods and conditions during the calculations, we outlined our concerns on the prospects and future challenges of DFT calculations in electrocatalysis studies.

Many molecular design tasks benefit from fast and accurate calculations of quantum-mechanical (QM) properties. However, the computational cost of QM methods applied to drug-like molecules currently renders large-scale applications of quantum chemistry challenging. Aiming to mitigate this problem, we developed DelFTa, an open-source toolbox for the prediction of electronic properties of drug-like molecules at the density functional (DFT) level of theory, using Δ-machine-learning. Δ-Learning corrects the prediction error (Δ) of a fast but inaccurate property calculation. DelFTa employs state-of-the-art three-dimensional message-passing neural networks trained on a large dataset of QM properties. It provides access to a wide array of quantum observables on the molecular, atomic and bond levels by predicting approximations to DFT values from a low-cost semiempirical baseline. Δ-Learning outperformed its direct-learning counterpart for most of the considered QM endpoints. The results suggest that predictions for non-covalent intra- and intermolecular interactions can be extrapolated to…

for polyethylene terephthalate (PET) in water, and the maximum enhancement factor (EF) can reach 360.5. Furthermore, the practicability of the developed method has been proved by the successful detection of MPs in tap water and pond water. This research provides an easy process, high sensitivity, and good reproducibility method for MP detection.

]. While the Raman signatures of neutral P3HT and singly charged P3HT segments (polarons) are known, the Raman spectra of doubly charged P3HT segments (bipolarons) are not yet sufficiently understood. Combining Raman spectroscopy measurements on doped P3HT thin films with first-principles calculations on oligomer models, we explain the evolution of the Raman spectra from neutral P3HT to increasingly doped P3HT featuring polarons and eventually bipolarons at high doping levels. We identify and explain the origin of the spectral features related to bipolarons by tracing the Raman signature of the symmetric collective vibrations along the polymer backbone, which - compared to neutral P3HT - redshifts for polarons and blueshifts for bipolarons. This is explained by a planarization of the singly charged P3HT segments with polarons and rather high order in thin films, while the doubly charged segments with bipolarons are located in comparably disordered regions of the P3HT film due to the high dopant concentration. Furthermore, we identify additional Raman peaks associated with vibrations…

Co XANES data analysis. As a result, we obtained quantitative structural information of the SAC nearest atomic environment, thereby extending the NN-XANES approach previously demonstrated for nanoparticles and size-selective clusters.

dimethyl sulfoxide (DMSO). There are various (and often conflicting) explanations of this effect suggested in the experimental literature, but its theoretical understanding based on simulation and modelling accounting for the complex realistic morphology of PEDOT : PSS is missing. Here, we report Martini coarse-grained molecular dynamics simulation for the DMSO solvent treatment of the PEDOT : PSS film. We show that during solvent treatment a part of the deprotonated PSS chains are dissolved in the electrolyte. After the solvent treatment and subsequent drying, the PEDOT-rich regions become closer to each other, with a part of the PEDOT chains penetrating into the PSS-rich regions. This leads to an efficient coupling between PEDOT-rich regions, leading to the enhancement of the conductivity. Another factor leading to the conductivity improvement is the π-π stacking enhancement resulting in more π-π stacks in the film and in the increased average size of PEDOT crystallites. Our results demonstrate that course-grained molecular dynamics simulations of a realistic system represent a…

A neural network potential (NNP) is developed to investigate the complex reaction dynamics of RDX thermal decomposition. Our NNP model is proven to possess good computational efficiency and retain the ab initio accuracy, which allows the investigation of the entire decomposition process of bulk RDX crystal from an atomic perspective. A series of molecular dynamics (MD) simulations are performed on the NNP to calculate the physical and chemical properties of the RDX crystal. The results show that the NNP can accurately describe the physical properties of RDX crystal, like cell parameters and equation of state. The simulations of RDX thermal decomposition reveal that the NNP could capture the evolution of species at the ab initio accuracy. The complex reaction network was established, and a reaction mechanism of RDX decomposition was provided. The N-N homolysis is the dominant channel, which cannot be observed in previous DFT studies of gas RDX. In addition, the H abstraction reaction by NO2 is found to be the critical pathway for NO and H2O formation, while the HONO elimination is…

, Hirshfeld charge analysis) do not demonstrate the statistical normality. Furthermore, we illustrate that MESP can be extensively adopted to strengthen the validity of the linear free energy relationships (LFERs) under various chemical conditions. The results revealed that the MESP shift derived by a functional group on a mono-substituted benzene ring is a strong predictor for the substituent effects on the electronic behaviours in chemical reactions; thus, it can serve as an alternative to other empirical parameters such as the Hammett or Swain-Lupton parameters, or the charge shift.

Lithium decoration enhances the hydrogen storage capacities, reversibility and diffusion kinetics of t-boron nitride monolayer.

Recent advances in the development of reactive machine-learned potentials (MLPs) promise to transform reaction modelling. However, such methods have remained computationally expensive and limited to experts. Here, we employ different MLP methods (ACE, NequIP, GAP), combined with automated fitting and active learning, to study the reaction dynamics of representative Diels-Alder reactions. We demonstrate that the ACE and NequIP MLPs can consistently achieve chemical accuracy (± 1 kcal mol−1) to the ground-truth surface with only a few hundred reference calculations. These strategies are shown to enable routine ab initio-quality classical and quantum dynamics and obtain dynamical quantities such as product ratios and free energies from non-static methods. For ambimodal reactions, product distributions were found to be strongly dependent on the QM method and less so on the type of dynamics propagated.

where M = Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, and Co, A = Al, Ga, and In, and B is boron). The thermodynamic stability of seven previously synthesized MAB phases is confirmed, three additional phases are predicted to be stable, and 23 phases are found to be close to stable. Furthermore, the crystal symmetry preference for forming orthorhombic or hexagonal crystal structures is investigated where the considered Al-based MAB phases tend to favour orthorhombic structures whereas Ga- and In-based phases in general prefer hexagonal structures. The theoretically predicted stable MAB phases along with the structural preference is intended to both guide experimental efforts and to give an insight into the stability for different crystal symmetries of MAB phases.

, but it qualitatively described the trends in reaction barriers and energies. Importantly, we established that accurate yet efficient meta-hybrid or double-hybrid DFT potential energy surfaces can be acquired based on geometries from the computationally efficient and robust BP86/DZP level.

], switching rate, and other properties. The mechanisms of controlling or driving functional systems, which involve acid-base reactions, acid catalyzed reactions, ionic bonding, coordination bonding, hydrogen bonding, ion exchange, cation-π interaction, solubility, swellability, permeability, and pH change in biosystems, are described. Applications of mPAHs in the chemical, material, energy, biotechnology and biomedical fields published in the past 5 years are reviewed. Prospects in the development and application of mPAHs are discussed.

, respectively. Furthermore, the average voltage of the bilayer TZACOF as the electrode material for SIBs and CIBs is found to be 0.96 and 1.13 V, respectively. Based on the results of rich electronic properties, low diffusion barriers, high storage capacity, and low average voltage, we can reach at the conclusion that the bilayer TZACOF may be a suitable candidate for use as an anode material for sodium and calcium ion batteries (SIBs and CIBs).

could effectively lower the overpotential of the oxygen evolution reaction, thus ensuring the overall water redox reaction to be achieved spontaneously under light irradiation. Our findings suggest that the CSHS is a promising water splitting photocatalyst.

approaches for the simulation of TRPES signals has enabled the interpretation of these transient spectra in terms of underlying coupled electronic-nuclear dynamics. In this perspective, we discuss the current state-of-the-art approaches, including efforts to push femtosecond pulses into vacuum ultraviolet and soft X-ray regimes as well as the utilization of novel polarizations to use time-resolved optical activity as a probe of nonadiabatic dynamics. We close this perspective with a forward-looking prospectus on the new areas of application for this technique.

-direction shows that the quadruple-PIT window can be produced by the strong destructive interference between the bright mode and the dark mode. The spectral response characteristics of the quadruple-PIT effect are numerically and theoretically investigated, and the results obtained by the finite-difference time-domain (FDTD) simulation fit well with that by the coupled mode theory (CMT) calculation. In addition, two hepta-frequency asynchronous switches are achieved by tuning the Fermi energy of the graphene, and their maximum modulation depths are 98.9% and 99.7%, corresponding to the insertion losses of 0.173 dB and 0.334 dB, respectively. Further studies show that polarization light has a significant impact on the quadruple-PIT, resulting in a polarization-sensitive switch being realized with a maximum modulation depth of 99.7% and a minimum insertion loss of 0.048 dB. In addition, when the Fermi energy is equal to 1.2 eV, the maximum time delay and group refractive index of the quadruple-PIT can be respectively as high as 1.065 ps and 3194, and the maximum delay-bandwidth…

-type lead-free halide perovskite materials, especially in optoelectronic devices. The article first introduces the lattice and energy band structure, the optoelectronic properties of lead-free perovskites, including the research method of lead-free perovskites, and then analyzes the reasons for the low luminous efficiency and poor stability of lead-free perovskite materials. Second, the development history and current situation of lead-free perovskites in different optoelectronic device applications are summarized. Finally, we present the challenges and prospects for the future development of lead-free perovskites.

We have investigated the origin of the unexpected, recently discovered phenomenon of reaction rate acceleration in water microdroplets relative to bulk water. Acceleration factors for reactions of atmospheric and synthetic relevance can be dissected into elementary contributions thanks to the original and versatile kinetic model. The microdroplet is partitioned in two sub-volumes, the surface and the interior, operating as interconnected chemical reactors in the fast diffusion regime. Reaction rate acceleration and its dependence on reaction molecularity and microdroplet dimensions are explained by applying transition-state-theory at thermodynamic equilibrium. We also show that our model, in combination with experimental measurements of rate acceleration factors, can be used to obtain chemical kinetics data at the air-water interface, which has been a long-standing challenge for chemists.

Here we report the synthesis of (Tm + Ta) co-doped TiO 2 ceramic by SSR method. Grain effect (EPDD), grain boundary effect (IBLC) and electrode effect all contributes to the colossal permittivity (CP) in (Tm + Ta) codoped TiO 2 ceramics.

seems to be more influenced by the interplay between the cation charge/radius and the polymer structure. The trends observed are in excellent agreement with previously observed transference numbers, confirming the importance and its connection to the ion transport in SPEs.

The latest applications of non-thermal plasma in photocatalysis were summarized, including the modification and synthesis of photocatalysts. Also, the challenges and outlook of this synergistic technology were discussed.

-SCR reaction, hoping to narrow the gap between the novel manganese oxide-based catalysts and the actual demands and realize commercialized application in the nearest future.

calculations for a single SMM. A semi-quantitative crystal field (CF) analysis is performed and shown here to be capable of indicating the general trends in a more chemically intuitive way. This analysis could help to identify the most important coordinating atoms for both diagonal and non-diagonal CF components. Thus, it could give some direct clues for improving the SMM properties: reducing the distance of the axial atom to the central ion, rotating the axial atom closer to the easy axis or increasing the amount of its negative charge. Correspondingly, opposite operations on the equatorial atom could give the same result.

-dimethylformamide have been correlated against newly measured experimental data. In addition to the calculations performed using density functional theory (DFT), the performance of different semi-empirical density functional tight binding (DFTB) approaches has been critically assessed. It was shown that the SCC DFTB/3ob parametrization in conjunction with the COSMO solvation model provides a highly adequate description of the electrochemical potentials also in the case of the two-fold reduced species. While the quality in the correlation against the experimental data proved to be slightly inferior compared to the employed DFT approach, the highly advantageous cost-accuracy ratio of the SCC DFTB/3ob/COSMO framework has important implications in the formulation of hierarchical screening strategies for materials associated with organic electronics. Based on the observed performance, the low-cost method provides sufficiently accurate results to execute efficient pre-screening protocols, which may then be followed by a DFT-based refinement of the best candidate structures to facilitate…

Nanocomposite materials consist of nanometer-sized quantum objects such as atoms, molecules, voids or nanoparticles embedded in a host material. These quantum objects can be exploited as a super-structure, which can be designed to create material properties targeted for specific applications. For electromagnetism, such targeted properties include field enhancements around the bandgap of a semiconductor used for solar cells, directional decay in topological insulators, high kinetic inductance in superconducting circuits, and many more. Despite very different application areas, all of these properties are united by the common aim of exploiting collective interaction effects between quantum objects. The literature on the topic spreads over very many different disciplines and scientific communities. In this review, we present a cross-disciplinary overview of different approaches for the creation, analysis and theoretical description of nanocomposites with applications related to electromagnetic properties.

Hydrogenation-induced semiconductor to metal transformation in two-dimensional phosphorus carbide PC 3 was predicted, and HPC 3 exhibits phonon-mediated superconductivity with high T c .

Orthorhombic LaFeO 3 and LaFe 0.9 Mn 0.1 O 3 prepared by solution combustion synthesis with ODH fuel show weak ferromagnetism with M m values of 0.48 and 4.3 emu g −1 at 12 kOe and paramagnetic behavior is noticed in rhombohedral LaMnO 3 prepared by same method.

chromophores according to experimental data, an excellent agreement between calculated and experimental linear absorption and circular dichroism spectra of WSCP is obtained. The effect of the mutual polarization of the pigment ground states is calculated to be very small. The simple Poisson-Transition-charge-from-Electrostatic-potential (Poisson-TrEsp) method is found to accurately describe the screening part of the excitonic coupling, obtained with FMO/PCM. Taking into account that the reaction field effects of the latter method can be described by a scalar constant leads to an improvement of Poisson-TrEsp that is expected to provide the basis for simple and realistic calculations of optical spectra and energy transfer in photosynthetic light-harvesting complexes. In addition, we present an expression for the estimation of Huang-Rhys factors of high-frequency pigment vibrations from experimental fluorescence line-narrowing spectra that takes into account the redistribution of oscillator strength by the interpigment excitonic coupling. Application to WSCP results in corrected…

present good stability. The current work has shed light onto the mechanism of water splitting on the surface of phosphide with vacancies. Our study suggests that engineering vacancies on CoP is a feasible route to improve its catalytic activity.

We investigate the effect of rotational inertia on the collective phenomena of underdamped active systems and show that the increase of the moment of inertia of each particle favors non-equilibrium phase coexistence, known as motility induced phase separation, and counteracts its suppression due to translational inertia. Our conclusion is supported by a non-equilibrium phase diagram (in the plane spanned by rotational inertial time and translational inertial time) whose transition line is understood theoretically through scaling arguments. In addition, rotational inertia increases the correlation length of the spatial velocity correlations in the dense cluster. The fact that rotational inertia enhances collective phenomena, such as motility induced phase separation and spatial velocity correlations, is strongly linked to the increase of rotational persistence. Moreover, large moments of inertia induce non-monotonic temporal (cross) correlations between translational and rotational degrees of freedom truly absent in non-equilibrium systems.

for benzene, using gauge-including atomic orbitals and canonical molecular orbitals (CMOs). The orbital contributions to nuclear magnetic shielding tensors are usually estimated by employing a natural chemical shielding (NCS) analysis in NLMO or CMO bases. The RVE approach shows that the core contribution to the magnetic response is small and localized at the nuclei, contrary to what NCS calculations suggest. This may lead to a completely incorrect interpretation of the magnetic σ-orbital response of nonplanar structures, which may play a major role in the overall magnetic shielding of the system. The RVE approach is thus a simple and inexpensive way to determine the magnetic response of the core- and σ-electrons.

show the suitability of the SnS monolayer for SIBs. In addition, the low activation barrier for Na migration (0.13 eV) is attractive for a fast sodiation/desodiation process. Henceforth, these encouraging outcomes suggest the application of the SnS sheet as an excellent anode for next-generation SIBs.

electrode. Our work provides clear mechanistic evidence that both terminations of the MXene electrodes and functional groups of the IL electrolytes affect the interfacial structures and the EDL formation, further leading to the different supercapacitor performance, which will be helpful in designing highly efficient energy-storage devices.

= 0.79, RMSE = 1.40, and SD = 1.35 on the test set. Comparing DLSSAffinity with the existing state-of-the-art deep learning-based binding affinity prediction methods, the DLSSAffinity model outperforms other models. These results demonstrate that combining global sequence and local structure information as the input features of a deep learning model can improve the accuracy of protein-ligand binding affinity prediction.

Ambipolar transistor properties have been observed in various small-molecule materials. Since a small energy gap is necessary, many types of molecular designs including extended π-skeletons as well as the incorporation of donor and acceptor units have been attempted. In addition to the energy levels, an inert passivation layer is important to observe ambipolar transistor properties. Ambipolar transport has been observed in extraordinary π-electron systems such as antiaromatic compounds, biradicals, radicals, metal complexes, and hydrogen-bonded materials. Several donor/acceptor cocrystals show ambipolar transport as well.

A ReaxFF force field has been developed for metal carbonates (CaCO 3 , MgCO 3 and Na 2 CO 3 ) and is used for molecular dynamics simulations to study their behavior in aqueous solution at ambient and supercritical conditions.

adsorption and activation. Moreover, the screened SACs possess good dispersity and thermodynamic stability. Our work provides a promising solution for the efficient screening and rational design of high-performance electrocatalysts toward the NRR.

We discuss and examine the stability, electronic properties, and transport characteristics of asymmetric monolayers XWGeN 2 (X = O, S, Se, Te) using ab initio density functional theory.

Lithium-sulfur batteries (LSBs) are promising energy storage devices because of their high theoretical capacity and energy density. However, the "shuttle" effect in lithium polysulfides (LiPSs) is an unresolved issue that can hinder their practical commercial application. Research on LSBs has focused on finding appropriate materials that suppress this effect by efficiently anchoring the LiPSs intermediates. Quantum chemical computations are a useful tool for understanding the mechanistic details of chemical interaction involving LiPSs, and they can also offer strategies for the rational design of LiPSs anchoring materials. In this perspective, we highlight computational and theoretical work performed on this topic. This includes elucidating and characterizing the adsorption mechanisms, and the dominant types of interactions, and summarizing the binding energies of LiPSs on anchoring materials. We also give examples and discuss the potential of descriptors and machine learning approaches to predict the adsorption strength and reactivity of materials. We believe that both approaches…

The emergence of state-of-the-art X-ray light sources has paved the way for novel spectroscopies that take advantage of their atomic specificity to shed light on fundamental physical, chemical, and biological processes both in the static and time domains. The success of these experiments hinges on the ability to interpret and predict core-level spectra, which has opened avenues for theory to play a key role. Over the last two decades, linear-response time-dependent density functional theory (LR-TDDFT), despite various theoretical challenges, has become a computationally attractive and versatile framework to study excited-state spectra including X-ray spectroscopies. In this context, we focus our discussion on LR-TDDFT approaches for the computation of X-ray Near-Edge Structure (XANES), Valence-to-Core X-ray Emission (VtC-XES), and Resonant Inelastic X-ray Scattering (RIXS) spectroscopies in molecular systems with an emphasis on Gaussian basis set implementations. We illustrate these approaches with applications and provide a brief outlook of possible new directions.

and the effective charge density of metal cations was established, which provides a better understanding of Lewis acidity. In short, this study not only offers two efficient acidity measurement methods but also provides a molecular basis for optimizing the performance of ADESs in applications.

Photoelectron spectroscopy has long been a powerful method in the toolbox of experimental physical chemistry and molecular physics. Recent improvements in coincidence methods, charged-particle imaging, and electron energy resolution have greatly expanded the variety of environments in which photoelectron spectroscopy can be applied, as well as the range of questions that can now be addressed. In this Perspectives Article, we focus on selected recent studies that highlight these advances and research areas. The topics include reactive intermediates and new thermochemical data, high-resolution comparisons of experiment and theory using methods based on pulsed-field ionisation (PFI), and the application of photoelectron spectroscopy as an analytical tool to monitor chemical reactions in complex environments, like model flames, catalytic or high-temperature reactors.

An overview of the ocean code for calculating near-edge X-ray spectroscopy, including X-ray absorption and resonant inelastic X-ray scattering, using the Bethe-Salpeter equation approach.

Paramagnetic NMR data contain extremely accurate long-range information on metalloprotein structures and, when used in the frame of integrative structural biology approaches, they allow for the retrieval of structural details to a resolution that is not achievable using other techniques. Paramagnetic data thus represent an extremely powerful tool to refine protein models in solution, especially when coupled to X-ray or cryoelectron microscopy data, to monitor the formation of complexes and determine the relative arrangements of their components, and to highlight the presence of conformational heterogeneity. More recently, theoretical and computational advancements in quantum chemical calculations of paramagnetic NMR observables are progressively opening new routes in structural biology, because they allow for the determination of the structure within the coordination sphere of the metal center, thus acting as a loupe on sites that are difficult to observe but very important for protein function.

> 1), coupled to a spin-1/2 electronic ancilla for error detection. By thorough numerical simulations we show that a significant gain in the effective phase memory time can be achieved. This is further enhanced by exploiting pulse-shaping techniques to reduce the leakage and/or the impact of decoherence during correction. Moreover, we simulate the implementation of single-qubit operations on the encoded states.

The S66x8 noncovalent interactions benchmark has been re-evaluated at the “sterling silver” level. Against this, a selection of computationally more economical alternatives has been assayed, ranging from localized CC to double hybrids and SAPT(DFT).

The electronic structures, DOSs, carrier transport properties, and optical properties of CsGeX 3 (X = I, Br or Cl) perovskites under triaxial strains of −4% to 4% were investigated based on density functional theory.

elimination. Variation of the cluster elemental composition can be a powerful method to identify how the propensity of the critical first step of NO dissociation can be increased. The testing of such concepts with atomic detail can be of great help in guiding the choices in rational catalyst design.