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The solid electrolyte interphase (SEI) is a thin heterogeneous layer formed at the anode/electrolyte interface in lithium‐ion batteries as a consequence of the reduction of the electrolyte. The initial formation of the SEI inhibits the direct contact between the electrode and the electrolyte and thus protects the battery. However, the composition, structure, and size of the SEI evolve over time and the growth of the SEI is considered the primary mechanism leading to the gradual deterioration of the battery performance. Despite the importance of the SEI and its growth, the atomistic understanding of the underlying elementary reaction steps remains partial. Molecular modeling of the electrolyte decomposition is key to gain detailed insights that are complementary to experiments for the reactions occurring in this heterogenous interphase. In this perspective, the electron transport mechanisms are first described from the anode to the electrolyte through the SEI and highlight the importance of the inorganic/organic interface within the heterogeneous SEI: it is where the electrolyte decomposition reactions are likely to occur. Finally, a view is provided on the current progress on molecular modeling techniques (e.g., Density Functional Theory, force fields, machine learning potentials) of the SEI and the challenges each method faces. [ABSTRACT FROM AUTHOR]

Ligand-decorated metal surfaces play a pivotal role in various areas of chemistry, particularly in selective catalysis. Molecular dynamics simulations at the molecular mechanics level of theory are best adapted to gain complementary insights to experiments regarding the structure and dynamics of such organic films. However, standard force fields tend to capture only weak physisorption interactions. This is inadequate for ligands that are strongly adsorbed such as carboxylates on metal surfaces. To address this limitation, we employ the Gaussian Lennard-Jones (GLJ) potential, which incorporates an attractive Gaussian potential between the surface and ligand atoms. Here, we develop this approach for the interaction between cobalt surfaces and carboxylate ligands. The accuracy of the GLJ approach is validated through the analysis of the interaction of oxygen with two distinct cobalt surfaces. The accuracy of this method reaches a root mean square deviation (RMSD) of about 3 kcal/mol across all probed configurations, which corresponds to a percentage error of roughly 4%. Application of the GLJ force field to the dynamics of the organic layer on these surfaces reveals how the ligand concentration influences the film order, and highlights differing mobility in the x and y directions, attributable to surface corrugation on Co(11 2 ̄ 0). GLJ is versatile, suitable for a broad range of metal/ligand systems, and can, subsequently, be utilized to study the organic film on the adsorption/desorption of reactants and products during a catalytic process. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations explore the stability of a single platinum atom on various flat, stepped, and defective ceria surfaces, in the context of single‐atom catalysts (SACs) for the water–gas shift (WGS) reaction. The adsorption properties and diffusion kinetics of the metal strongly depend on the support termination with large stability on metastable and stepped CeO2(100) and (210) surfaces where the diffusion of the platinum atom is hindered. At the opposite, the more stable CeO2(111) and (110) terminations weakly bind the platinum atom and can promote the growth of metallic clusters thanks to fast diffusion kinetics. The adsorption of carbon monoxide on the single platinum atom supported on the various ceria terminations is also sensitive to the surface structure. Carbon monoxide weakly binds to the single platinum atom supported on reduced CeO2(111) and (211) terminations. The desorption of the CO2 formed during the WGS reaction is thus facilitated on the latter terminations. A vibrational analysis underlines the significant changes in the calculated scaled anharmonic CO stretching frequency on these catalysts. [ABSTRACT FROM AUTHOR]

Solvent effects are notoriously difficult to describe for metallic nanoparticles (NPs). Here, we introduce GAL21 which is the first pairwise additive force field that is specifically designed to modulate the near chemisorption energy of water as a function of the coordination numbers of the metallic atoms. We find a quadratic dependence to be most suitable for capturing the dependence of the adsorption energy of water on the generalized coordination number (GCN) of the metal atoms. GAL21 has been fitted against DFT adsorption energies for Cu, Ag, Au, Ni, Pd, Pt, and Co on 500 configurations and validated on about 3000 configurations for each metal, constructed on five surfaces with GCNs varying from 2.5 to 11.25. Depending on the metals, the root mean square deviation is found between 0.7 kcal mol−1 (Au) to 1.6 kcal mol−1 (Ni). Using GAL21, as implemented in the open-source code CP2K, we then evaluate the solvation energy of Au55 and Pt55 NPs in water using thermodynamic integration. The solvation free energy is found to be larger for Pt than for Au and systematically larger than 200 kcal mol−1, demonstrating the large impact of solvent on the surface energetics of NPs. Still, given that the amorphous NPs are both, the most stable and the most solvated ones, we do not predict a change in the preferred morphology between the gas-phase and in water. Finally, based on a linear regression on three sizes of NPs (from 38 to 147), the solvation energy for Au and Pt surface atoms is found to be −5.2 and −9.9 kcal mol−1, respectively. [ABSTRACT FROM AUTHOR]

To better identify the distinctive characteristics of space representation in the radial dimension, we have proposed a new paradigm: the landmarks alignment task where two parallel aluminum bars were radially presented. Children had to move a landmark along one bar and place it at the same location as the reference landmark placed by the examiner on the parallel bar. The major interest of this task was its capacity to assess space representation in the radial dimension when considering a spatial landmark that oriented the subject's attention toward the orthogonal dimension. The most important result showed that in the radial dimension children with dyslexia exhibited a forward bias on the left bar, meaning a mental underrepresentation of the leftward peripersonal space and/or a mental overrepresentation of the rightward peripersonal space. Furthermore, reading discrepancies were correlated with radial forward bias on the left bar. The experiment was also conducted in the lateral axis, showing a pseudoneglect behavior in children without dyslexia. Our landmarks alignment task had the advantage of being able to assess space representation in a complex environment. The forward radial representational bias in children with dyslexia could have implications for spatial orientation in peripersonal workspace in school situations. [ABSTRACT FROM AUTHOR]

Electrochemical synthesis could provide an elegant and efficient means to exploit the largely available C1 building block CO 2 . The electrocarboxylation of dienes is, in particular, an attractive goal. However, the presently known electrocatalysts are inefficient and not very selective since they work around −2.3 V vs. SHE. In order to identify more active catalysts, we need to better understand the reaction mechanism. In this contribution, we present prototypical experimental results for the electrocarboxylation of 2,3-dimethyl-butadiene on a Ni catalyst and quantify the side-products, namely carbonates, oxalic and formic acid. Together with the extensive, state of the art, first principles investigation of the mechanism at the atomic scale, we reveal a highly activated process around the onset potential of −1.3 V and a change in mechanism at the peak potential of −2.3 V, suggesting that a more active catalyst could be engineered by modifying the morphology in order to facilitate the “chemical” C C coupling step. [ABSTRACT FROM AUTHOR]

The main objective of the present study was to determine the minimal optical deviation responsible for cognitive after-effects in healthy individuals and to explore whether there was a relationship between the degree of optical deviation and cognitive after-effects. Therefore different leftward optical deviations (8°, 10° and 15°) were used in three different groups of healthy participants. Sensorimotor after-effects (evaluating the visuo-manual realignment) were assessed using an open-loop pointing task and cognitive after-effects (evaluating changes in spatial representation) were assessed using manual and perceptual (landmark) line bisection tasks. Results revealed that exposure to 8°, 10° and 15° optical shifts produced sensorimotor after-effects. In contrast, the occurrence of cognitive after-effects depended on the optical deviation. Adaptation to an 8° leftward optical deviation did not produce cognitive after-effects. Adaptation to a 10° leftward optical deviation was responsible for after-effects in the manual line bisection task only. Adaptation to a 15° leftward optical deviation produced after-effects in both the manual and perceptual line bisection tasks. All cognitive after-effects were rightward and were similar to mild, neglect-like manifestations. Both sensorimotor and cognitive after-effects were correlated with the degree of optical deviation. Our results are of methodological and theoretical interest to those interested in sensorimotor plasticity and spatial cognition. [ABSTRACT FROM AUTHOR]

Themost challenging step in the production of acrylates from ethyleneand CO2mediated by transition-metal complexes is the releaseof the acrylate from the metallalactone intermediate formed by couplingof ethylene and CO2. Recently, methyl acrylate formationwas achieved from nickelalactones by using methyl iodide (MeI) asthe electrophile, and the yield was tuned with different amine andphosphine ligands. Modeling organometallic catalysts with such largeligands accurately is a challenge for computational chemistry. A hybridapproach has been designed here by coupling the double hybrid XYG3and the hybrid B3LYP exchange correlation functionals, using the extendedONIOM scheme. This approach was then applied to explore the role ofthe MeI electrophile for the formation of methyl acrylate from theinitial nickelalactone complex and to rationalize the effect of theligands on the yield of methyl acrylate. We show that the choice ofligand has little effect on the main productive pathway. However,it has a significant influence on side reactions, which compete withthe productive pathway and are detrimental to methyl acrylate formation.Finally, the need for a very large overstoichiometry of MeI for agood yield of methyl acrylate is explained by the lower polarity ofMeI, which avoids the stabilization of nonproductive intermediates.The nature of the limiting intermediates has been validated by comparingcalculated and experimental vibrational spectra. [ABSTRACT FROM AUTHOR]

While Ru is a poor hydrogenation catalyst compared to Pt or Pd in the gas phase, it is efficient under aqueous phase conditions in the hydrogenation of ketones such as the conversion of levulinic acid into gamma-valerolactone. Combining DFT calculations and experiments, we demonstrate that water is responsible for the enhanced reactivity of Ru under those conditions. [ABSTRACT FROM AUTHOR]

Highlights: [•] DFT shows how the environment of the active sites can tune the catalytic reactivity. [•] Alloying Pt with Sn (or Pd with Au) weakens butene adsorption and increases selectivity for butadiene partial hydrogenation. [•] On PtSn, the non-selective pathway for butadiene hydrogenation through a metallacycle intermediate is disadvantaged. [•] For alcohol dehydrogenation, co-adsorbed water plays a key role in assisting OH bond breaking. [Copyright &y& Elsevier]

In the oxidation of alcohols with TEMPO as catalyst, the substrate has alternatively been postulated to be oxidized but uncoordinated TEMPO+ (Semmelhack) or Cu-coordinated TEMPO• radical (Sheldon). The reaction with the Cu(bipy)2+/TEMPO cocatalyst system has recently been claimed, on the basis of DFT calculations, to not be a radical reaction but to be best viewed as electrophilic attack on the alcohol C-Hα bond by coordinated TEMPO+. This mechanism combines elements of the Semmelhack mechanism (oxidation of TEMPO to TEMPO+) and the Sheldon proposal ("in the coordination sphere of Cu"). The recent proposal has been challenged on the basis of DFT calculations with a different functional, which were reported to lead to a radical mechanism. We carefully examine the results for the two functionals and conclude from both the calculated energetics and from an electronic structure analysis that the results of the two DFT functionals are consistent and that both lead to the proposed mechanism with TEMPO not acting as radical but as (coordinated) positive ion. [ABSTRACT FROM AUTHOR]

Schizophrenia patients demonstrate behavioural and cerebral lateralised anomalies, prompting some authors to suggest they exhibit a mild form of right unilateral neglect. To better describe and understand lateralised visuospatial anomalies in schizophrenia, three experiments were run using tasks often utilised to study visuospatial processing in healthy individuals and in neglect patients: the Behavioural Inattention Test (BIT), the manual line bisection task with and without a local cueing paradigm, the landmark task (or line bisection judgement), and the number bisection task. Although the schizophrenia patients did not exhibit the full-blown neglect syndrome, they did demonstrate marked spatial biases that differentiated them from controls on all but two tasks. More specifically, schizophrenia patients showed neither a simple perceptual deficit nor an asymmetry, but demonstrated (1) lateralised anomalies on a simple manual line bisection task; (2) unilateral attentional deficits for line bisection within a local cueing paradigm; and (3) a lateralised deficit in the visuospatial representations of numbers. Altogether, these results suggest a right hemineglect-like deficit in schizophrenia in attentional, representational, and motor-intentional processes. Yet it does not appear to be as strong a phenomenon. Indeed, it could be considered as an accentuation of the normal asymmetry in visuospatial processing. [ABSTRACT FROM AUTHOR]

We have investigated the reaction mechanism of the selective aerobic oxidation of primary alcohols into aldehydes using a bipy-copper complex and the 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) radical as cocatalysts (Gamez et al. Chem. Commun. 2003, 2412–2415) and compared it to the well-known oxidation by the TEMPO ion. Our theoretical investigation shows that (a) the oxidation of alcohols to aldehydes by uncoordinated TEMPO+ takes place by electrophilic attack on the C–Hα. bond of the alcohol; (b) the Cu(bipy)2+ complex has two functions, namely, (1) it acts as a template that brings TEMPO and the (deprotonated) alcohol in proximity by coordinating these moieties in adjacent coordination sites, and (2) it oxidizes the TEMPO radical to (coordinated) TEMPO ion. The H abstraction from alcohol by TEMPO+ then proceeds as an intramolecular reaction, very much analogous to one of the reaction pathways with free TEMPO+ and with a remarkably low barrier. We stress that compared to other A–H bonds (A=C, N, 0, F), the relatively high-lying C–H bonds are particularly susceptible to electrophilic attack, and notably the C–Hα. bond next to the 0 in an alcohol is so because it is pushed up by an 0 lone pair. Electrophilic attack, being common to the particular catalytic system studied in this paper and the well-known biotic and abiotic oxidation catalysis by heme and non-heme complexes of the ferryl (FeIVO2+) ion, appears to be a unifying electronic structure principle of C–Hα. hydroxylation and oxidation reactions. [ABSTRACT FROM AUTHOR]

Metaloxo species are often postulated as key active species in oxidative catalysis. Among all, the quintet FeO2+ moiety is particularly widespread and active: aliphatic C-H bonds undergo hydroxylation easily through a H-abstraction/O-rebound mechanism. The high electrophilicity of quintet FeO2+ originates from its electronic structure: a low lying vacant σ* can accept electronic density from the aliphatic C-H bond. What singles out this quintet FeO2+? Its lowest vacant acceptor orbital energy? its shape (σ* vs π*)? or has its biological importance more simply arisen from the high iron abundance? To answer those questions, we have performed density-functional theory calculations to study systematically the methane-to-methanol reaction catalyzed by MO(H2O)p2+ complexes (M V, Cr, Mn, Fe, Co, p = 5 and M = Ni, Cu, p = 4) in gas phase. We show here that the lower the MO2+ acceptor orbital lies in energy, the lower the H-abstraction barrier is in general. However, a cf acceptor orbital is much more efficient than a π acceptor orbital for a given energy. Finally, we found that indeed, the FeO2+ moiety is particularly efficient but also CoO2+ and MnO2+ could be good candidates to perform C-H hydroxylation. [ABSTRACT FROM AUTHOR]

Abstract: To gain insight into how fluorination of ligands alters the C–H and C–C reductive elimination from Pt(IV) octahedral complexes, metadynamics and static DFT calculations have been performed. We compare the C–H and C–C reductive elimination from Pt(IV) octahedral complexes L2Pt(CH3)3X (X=H or CH3, L2 diphosphine ligand, viz=model of dppe and dppbz ligand and its fluorinated versions). The use of metadynamics simulations is shown to be a powerful tool to describe the reactivity of organometallic compounds, and provide us with the activation free energy of the different processes involved in these reactions: ligand dissociation, C–C and C–H formation. The structural data for the complexes are compared and in the fluorinated complexes, the Pt–P distances are significantly shorter even if the Pt–P dissociation is less energetically demanding compared to the non-fluorinated complexes. The computed free activation energies from metadynamics calculations show that for C–H reductive eliminations direct mechanism and concerted mechanism can occur but the concerted pathway is more favorable. For the C–C reductive elimination, the dissociative pathway has been studied and the use of fluorinated complexes enhances the dissociation capability of the chelating ligand and so should improve the reactivity. We also report computed activation free energy with inclusion of the entropy effect for the dissociation of the diphosphine ligand, necessary step for the C–C reductive elimination. [Copyright &y& Elsevier]

In healthy subjects, sensorimotor after-effects of prism adaptation are known to be symmetric (they appear after using leftward and rightward optical deviations), whereas cognitive after-effects are asymmetric (they appear after using a leftward optical deviation) and rightward oriented. Sensorimotor and cognitive after-effects have been classically studied using different specific tasks. The purpose of the current study was to investigate whether both after-effects may be involved in a same visuo-spatial task. Therefore we compared the amplitude of after-effects following adaptation to a rightward or leftward optical deviation. After-effects were assessed by manual pointing or goal oriented locomotor task. The main result showed a greater amplitude for rightward locomotor after-effects (after adaptation to a leftward deviation) than for leftward locomotor after-effects (after adaptation to a rightward deviation). This means that cognitive after-effects may add to sensorimotor after-effects following adaptation to a leftward optical deviation. This asymmetry challenges the classical distinction between sensorimotor and cognitive after-effects of prism adaptation. Implications for the functional mechanisms and the neuroanatomical substrate of prism adaptation are discussed. [ABSTRACT FROM AUTHOR]

Abstract: We have performed a detailed study of the cyclization of carbonyl groups on unactivated alkynyl-quinolines. Two cyclization modes are accessible: the exo vs. endo mode. The influence of the substituents of the alkynyl-quinolines have been studied using two examples giving different reactivity: the phenyl and the CH2OMe substituent. From an experimental point of view, the reaction occurs in basic medium and the first step of the reaction has been shown to be the formation of the hemi-acetal. Two mechanisms have been investigated with and without deprotonation of the hemi-acetal prior to the carbon–oxygen bond formation and the proton’s transfer. The influence of the solvent effects has been studied using supermolecular and continuum/supermolecular techniques. The mechanism without deprotonation of the hemi-acetal presents high barriers and the inclusion of solvent effects both with the continuum method and the supermolecular approach stresses strongly this tendency especially when phenyl substituents are used. On the other hand, the base mechanism exhibits lower barriers but solvent effects also increase these barriers, which remain quite reasonable around 15kcalmol−1. Whatever the methods used, the exo mode of reaction appears to be the kinetic pathway whereas the endo mode appears to be under thermodynamic control. [Copyright &y& Elsevier]

Introduction. Numerous authors have reported the existence of lateralised abnormalities towards the right side in patients with schizophrenia. Methods. In the present study, a manual line bisection task was used to assess the existence of a visuospatial bias in patients with schizophrenia as compared to healthy subjects and left unilateral neglect patients. In addition, we used a local cueing paradigm (consisting of a number placed on the right, on the left, or at both ends of the line). Results. Healthy subjects showed a leftwards trend in the "no cue" condition (known as pseudoneglect) and neglect patients showed a right bias in all cue conditions. In contrast, patients with schizophrenia placed their manual estimation of the centre further to the left than healthy subjects in all cue conditions, reflecting neglect of the right side of the line. Moreover, like healthy subjects and neglect patients, patients with schizophrenia were affected by the local cueing. Conclusion. Hence, patients with schizophrenia show a bias in their spatial representation, which does not interfere with local context processing. [ABSTRACT FROM AUTHOR]

Neglect patients exhibit both a lack of awareness for the spatial distortions imposed during visuomanual prism adaptation procedures, and exaggerated postadaptation negative after-effects. To better understand this unexpected adaptive capacity in brain-lesioned patients, we investigated the contribution of awareness for the optical shift to the development of prism adaptation. The lack of awareness found in neglect was simulated in a multiple-step group where healthy subjects remained unaware of the optical deviation because of its progressive stepwise increase from 2° to 10°. We contrasted this method with the classical single-step group in which subjects were aware of the visual shift because they were directly exposed to the full 10° shift. Because the number of pointing trials was identical in the two groups, the total amount of deviation exposure was 50% larger in the single-step group. Negative after-effects were examined with an open-loop pointing task performed with the adapted hand, and generalization was tested with open-loop pointing with the nonexposed hand to visual and auditory targets. The robustness of adaptation was assessed by an open-loop pointing task after a simple deadaptation procedure. The progressive, unaware condition was associated with larger negative after-effects, transfer to the nonexposed hand for the visual and auditory pointing tasks, and greater robustness. The amount of adaptation obtained remained, nevertheless, lower than the exaggerated adaptive capacity seen in patients with neglect. Implications for the functional mechanisms and the anatomical substrates of prism adaptation are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The influence of carbon–carbon triple bond polarization on the regiochemistry of the Pauson–Khand reaction has been studied with the B3LYP functional. The regiochemistry determining step of this reaction, i.e., olefin insertion leading to cobaltacycle formation, has been examined with ethylene as the olefin and propyne, methyl 2-butynoate, and methyl propiolate as the acetylenes. From this study, it has been concluded that, in absence of overwhelming steric effects of an acetylene substituent, the regiochemistry is influenced by the polarization of the acetylenic bond, which arises from the different substituents. The initial C–C bond is preferentially formed with the acetylenic carbon that has the greater electron density: with propyne, this leads to a cyclopentenone having the methyl group in the α-position; with methyl 2-butynoate, to a cyclopentenone with the CO2Me in the β-position; with methyl propiolate, which is virtually unpolarized in the complex, to a cyclopentenone with the CO2Me in the α-position (a result of steric effects). These theoretical results are concordant with those observed experimentally with norbornene. The question of axial versus equatorial reactive positions for the coordinated olefin is also addressed and a kinetic simulation is presented. [Copyright &y& Elsevier]

Hemispatial neglect is a neurological deficit of perception, attention, representation, and/or performing actions within the left-sided space. The condition also produces many functional debilitating effects on everyday life, and is associated with poor functional recovery and inability to benefit from treatment. Numerous methods of rehabilitation (sensory stimulations or active training) have been proposed to alleviate neglect condition. It has been recently shown that visuo-manual adaptation to rightward optical shift leads to profound and enduring improvements of neglect symptoms. Based on the different methods commonly used in the rehabilitation of neglect, several techniques have been employed to simulate neglect symptoms in healthy subjects with a view to better understand the physiopathology of neglect. The present paper reviews studies of neglect-like behaviour in healthy individuals and in particular the use of prism adaptation as a procedure for simulating various symptoms of clinical neglect in normals. Neglect-like symptoms following prism adaptation offer insights as to the mechanisms of spatial neglect and provide an understanding of the interaction between low level sensorimotor processes and spatial cognition. Implications for the functional mechanisms and the anatomical substrates of prism adaptation are discussed in terms of inter-sensory plasticity and sensorimotor coordination and the way these may affect higher-level representations of space. [ABSTRACT FROM AUTHOR]

Rightward deviation on line bisection is considered one of the most classic clinical signs of unilateral visual neglect—a cognitive disorder of spatial processing that commonly follows right brain damage. Recently, short-term adaptation to wedge prisms has been shown to significantly reduce neglect on this and other conventional diagnostic tasks. Our previous study has shown that visuomotor adaptation in normals produces a similar pattern of directional bias on a line bisection task. Based on the good working knowledge of how neglect patients perform on different versions of the standard diagnostic task, we showed here that using leftward-deviating prisms in normals, it is possible to produce: (1) a reliable bias on line bisection, (2) a rightward specific deviation, (3) a modulation of rightward deviation, which depends on the relative spatial location of the target lines and (4) a line length effect. A final experiment confirmed that these after-effects are specific to prism adaptation rather than passive prism exposure. Collectively, these findings confirm that adaptation to left-deviating prisms in normals produces a reliable right-sided bias and as shown by a previous visuospatial judgement task, these findings cannot be adequately explained by the symmetric sensori–motor effects of prism adaptation. Taken together with the improvement of spatial neglect shown by right-deviating prisms only, the present study suggests that low level sensori–motor adaptations play a greater role in right hemisphere organisation for spatial cognition than previously thought. [Copyright &y& Elsevier]

The hydrogenation of CO 2 into high-value fuels is a potentially effective approach to reduce anthropogenic dependence on fossil fuels and effects of climate change. In this study, we evaluated the hydrogenation of CO 2 into CO and CH 4 under the electrochemical promotion of catalysis (EPOC) effect through experimental and computational studies using Ru nanoparticles. Ru nanoparticles (1–2 nm) supported on yttria-stabilized zirconia (YSZ) solid electrolyte were evaluated at 250 °C at atmospheric pressure. Under positive polarization, the methanation reaction was promoted and the competitive reverse water gas shift (RWGS) reaction was impeded. On the other hand, negative polarization resulted in suppressing permanently the methanation reaction and minimally affecting the RWGS reaction. To qualitatively rationalize the tuning of selectivity via EPOC, Density Functional Theory (DFT) computations were used to model the EPOC effect induced on the Ru (0001) surface. DFT computations uncovered that electric field effects together with a change in surface electrochemical potential between intermediates are responsible for the contrasting influence of EPOC on the CH 4 and CO formation over Ru catalysts. Image 1 [ABSTRACT FROM AUTHOR]

This paper evaluates simple schemes to extrapolate potential energy values using the set of energies and forces extracted from a molecular dynamics trajectory. In general, such a scheme affords the maximum amount of information about a molecular system at minimal computational cost. More specifically, schemes like this are very important in the field of adaptive multi-scale molecular dynamics simulations. In this field, often the computation of potential energy values at certain trajectory points is not required for the simulation itself, but solely for the a posteriori analysis of the simulation data. Extrapolating the values at these points from the available data can save considerable computational time. A set of extrapolation schemes are employed based on Taylor series and central finite difference approximations. The schemes are first tested on the trajectories of molecular systems of varying sizes, obtained at MM and QM level using velocity-Verlet integration with standard simulation time steps. Remarkably good accuracy was obtained with some of the approximations, while the failure of others can be explained in terms of the distinct features of a molecular dynamics trajectory. We have found that, for a Taylor expansion of the potential energy, both a first and a second order truncation exhibit errors that grow with system size. In contrast, the second order central finite difference approximation displays an accuracy that is independent of the size of the system, while giving a very good estimate of the energy, and costing as little as a first order truncation of the Taylor series. A fourth order central finite difference approximation requires more input data, which is not always available in adaptive multi-scale simulations. Furthermore, this approximation gives errors of similar magnitude or larger than its second order counterpart, at standard simulation time steps. This leads to the conclusion that a second order central finite difference approximation is the optimal choice for energy extrapolation from molecular dynamics trajectories. This finding is confirmed in a final application to the analysis of an adaptive multi-scale simulation. [ABSTRACT FROM AUTHOR]

Zeolites are essential materials to industry due to their adsorption and catalytic properties. The best current approach to prepare a targeted zeolite still relies on trial and error's synthetic procedures since a rational understanding of the impact of synthesis variables on the final structures is still missing. To discern the role of a variety of organic templates, we perform simulations of the early stages of condensation of silica oligomers by combining DFT, Brønsted‐Evans‐Polanyi relationships and kinetic Monte Carlo simulations. We investigate an extended reaction path mechanism including 258 equilibrium reactions and 242 chemical species up to silica octamers, comparing the computed concentrations of Si oligomers with 29SI NMR experimental data. The effect of the templating agent is linked to the modification of the intramolecular H‐bond network in the growing oligomer, which produces higher concentration of 4‐membered ring intermediates, precursors of the key double‐four ring building blocks present on more than 39 known zeolite topologies. [ABSTRACT FROM AUTHOR]

Zeolites are essential materials to industry due to their adsorption and catalytic properties. The best current approach to prepare a targeted zeolite still relies on trial and error's synthetic procedures since a rational understanding of the impact of synthesis variables on the final structures is still missing. To discern the role of a variety of organic templates, we perform simulations of the early stages of condensation of silica oligomers by combining DFT, Brønsted‐Evans‐Polanyi relationships and kinetic Monte Carlo simulations. We investigate an extended reaction path mechanism including 258 equilibrium reactions and 242 chemical species up to silica octamers, comparing the computed concentrations of Si oligomers with 29SI NMR experimental data. The effect of the templating agent is linked to the modification of the intramolecular H‐bond network in the growing oligomer, which produces higher concentration of 4‐membered ring intermediates, precursors of the key double‐four ring building blocks present on more than 39 known zeolite topologies. [ABSTRACT FROM AUTHOR]

To accelerate the conversion to more sustainable lubricants, there is a need for an improved understanding of the adsorption at the solid/liquid interface. As a first step, the density functional theory computed adsorption energies can be used to screen the ability of additives to cover a surface. Analogously to what has been found in catalysis with the universal scaling relations, we investigate here if a general universal ranking of additives can be found, independently of the surface considered. We divided our set of 25 diverse representative molecules into aprotic and protic molecules. We compared their adsorption over alumina and hematite, which are models of surface oxidized aluminum and steel, respectively. The adsorption energy ranking of our set is not strongly affected by alumina hydration. In contrast, adsorption on hematite is more strongly affected by hydration since all exposed Fe Lewis acid sites are converted into hydroxylated Brønsted basic sites. However, the ranking obtained on hydrated hematite is close to the one obtained on dry alumina, paving the road to a fast screening of additives. In our library, protic molecules are more strongly adsorbed than non-protic molecules. In particular, methyl and dimethyl phosphates are the most strongly adsorbed ones, followed by N-methyldiethanolamine, succinimide, and ethanoic acid. Additives combining these functional groups are expected to strongly adsorb at the solid/liquid interface and, therefore, likely to be relevant components of lubricant formulations. [ABSTRACT FROM AUTHOR]

The influence of the noble metal-support interaction on the performance, activation behavior and stability of Pd/CeO 2 catalysts for total methane oxidation was systematically investigated. A series of samples with 1–3 wt% Pd loading supported on CeO 2 with surface areas varying between 30 and 120 m2/g were tested as-prepared and after different reductive treatments. Distinct Pd structural states were identified, which influence the catalytic performance depending on the pre-treatment and the theoretical monolayer Pd coverage of CeO 2. Although reductive treatments improved the catalytic activity, the stability strongly depended on the Pd coverage on ceria and the type of reducing agent. A threshold of Pd concentration on the ceria surface was identified that ensures optimal noble metal efficiency, activity and long-term durability. Below this threshold, rapid catalyst deactivation occurs due to redispersion on the strongly interacting support whereas above this threshold Pd is prone to sintering irrespective of the atmosphere. [Display omitted] • Adjustment of Pd loading on CeO 2 is essential for high activity and stability. • Most efficient NM use is at loadings close to a monolayer coverage (∼0.4 mg/m2). • Below the Pd monolayer concentration, Pd redispersion leads to catalyst deactivation. • Above the optimum loading, NM sintering is encountered. • Oxidative and reductive treatments can be used to tune catalytic properties. [ABSTRACT FROM AUTHOR]

Developmental dyslexia affects almost 10% of school-aged children and represents a significant public health problem. Its etiology is unknown. The consistent presence of phonological difficulties combined with an inability to manipulate language sounds and the grapheme-phoneme conversion is widely acknowledged. Numerous scientific studies have also documented the presence of eye movement anomalies and deficits of perception of low contrast, low spatial frequency, and high frequency temporal visual information in dyslexics. Anomalies of visual attention with short visual attention spans have also been demonstrated in a large number of cases. Spatial orientation is also affected in dyslexics who manifest a preference for spatial attention to the right. This asymmetry may be so pronounced that it leads to a veritable neglect of space on the left side. The evaluation of treatments proposed to dyslexics whether speech or oriented towards the visual anomalies remains fragmentary. The advent of new explanatory theories, notably cerebellar, magnocellular, or proprioceptive, is an incentive for ophthalmologists to enter the world of multimodal cognition given the importance of the eye's visual input. [ABSTRACT FROM AUTHOR]

Abstract: Children with developmental dyslexia exhibit delayed reading abilities and various sensori-motor deficits. The way these various symptoms interact remain poorly understood. The objective of this study was twofold. First, we aimed to investigate whether postural control was impaired in dyslexic children when cognitive demands are increased. Second, we checked whether this effect could be reduced significantly by a treatment aiming to recalibrate ocular proprioception. Twelve dyslexic and fifteen treated dyslexic children (>3 months of treatment) were compared with twelve non-dyslexic children in two conditions (mean age: 11.6±2.1, 12.5±1.5 and 10.6±1.7 years respectively). In a first condition they maintained balance while fixating a point in front of them. In the second condition the postural task was combined with a silently reading one. Balance was assessed by means of a force plate. Results demonstrated that the mean velocity (i.e. the total length) of the center of pressure (CoP) displacement was increased in the reading task only for the dyslexic group. Interestingly, for the treated children, an inverse tendency was observed: the mean velocity (i.e. the total length) and the surface of the 90% confidence ellipse of the CoP displacement decreased for 13/15 patients and for 12/15 patients respectively, while performing the reading task. Values remained similar to those observed for the control children. Altogether, these results strongly suggest that cognitive demands can impair postural control in developmental dyslexia but this interaction could be normalized. These results sustain the hypothesis of a cerebellar origin for dyslexia. [Copyright &y& Elsevier]

Abstract: The 1,3-dipolar cycloadditions of cyclic nitrones to five-membered unsaturated lactones are studied. Special attention was focused on a single and double asymmetric induction when one or both components were chiral. The energies of the cycloaddition reactions are investigated through application of molecular orbital calculations at the B3LYP/6-31+G(d) theory level. A study of the different reactants’ approaches and their conformational aspects revealed the stereochemical preferences of these reactions. The results of these calculations correspond well with the previously reported experimental data. [Copyright &y& Elsevier]

Abstract: Transformation of aminoacridines into N-acridinyl-N′-alkylguanidines is described. The chosen procedure allows introduction of pendent substituents (exemplified by N,N-dimethylaminopropyl chain) into key acridinyl thioureas, thus opening the way to structural diversity. Spectroscopic study and pK a determination show that the presence of the strongly basic guanidine has a dramatic influence on the ionization of the acridine nucleus by lowering the pk a value down to 4.49. [Copyright &y& Elsevier]

Abstract: The 1,3-dipolar cycloaddition of cyclic nitrones with electron-poor and electron-rich cyclic dipolarophiles (α,β-unsaturated lactones and vinyl ethers) is studied. The energies of the cycloaddition reactions have been investigated through molecular orbital calculations at the B3LYP/6-31+G(d) level theory. Different reaction channels and reactants approaches, effective in regio- and stereochemical preferences are discussed. The results were compared with experimental data to find a good agreement. [Copyright &y& Elsevier]

Back Cover: Impact of Organic Templates on the Selective Formation of Zeolite Oligomers (Angew. DFT calculations, kMC method, non covalent interactions, templates, zeolite oligomerisation Keywords: DFT calculations; kMC method; non covalent interactions; templates; zeolite oligomerisation EN DFT calculations kMC method non covalent interactions templates zeolite oligomerisation 7448 7448 1 03/19/21 20210322 NES 210322 B DFT and kMC calculations b were combined to investigate the impact of the most commonly used organic template molecules both on the reaction energy profiles and the kinetics of formation of silica oligomers, as described by Caroline Mellot-Draznieks, Carlos Nieto-Draghi, and co-workers in their Research Article on page 7111. [Extracted from the article]

DFT calculations, kMC method, non covalent interactions, templates, zeolite oligomerisation Keywords: DFT calculations; kMC method; non covalent interactions; templates; zeolite oligomerisation EN DFT calculations kMC method non covalent interactions templates zeolite oligomerisation 7524 7524 1 03/23/21 20210322 NES 210322 B DFT- und kMC-Rechnungen b werden kombiniert, um die Reaktionsenergieprofile und die Bildungskinetik von Silika-Oligomeren zu untersuchen, wie Caroline Mellot-Draznieks, Carlos Nieto-Draghi et al. in ihrem Forschungsartikel auf S. 7187 beschreiben. Rücktitelbild: Impact of Organic Templates on the Selective Formation of Zeolite Oligomers (Angew. [Extracted from the article]

It well-known that mental training improves skill performance. Here, we evaluated skill acquisition and consolidation after physical or motor imagery practice, by means of an arm pointing task requiring speed-accuracy trade-off. In the main experiment, we showed a significant enhancement of skill after both practices (72 training trials), with a better acquisition after physical practice. Interestingly, we found a positive impact of the passage of time (+ 6 h post training) on skill consolidation for the motor imagery training only, without any effect of sleep (+ 24 h post training) for none of the interventions. In a control experiment, we matched the gain in skill learning after physical training (new group) with that obtained after motor imagery training (main experiment) to evaluate skill consolidation after the same amount of learning. Skill performance in this control group deteriorated with the passage of time and sleep. In another control experiment, we increased the number of imagined trials (n = 100, new group) to compare the acquisition and consolidation processes of this group with that observed in the motor imagery group of the main experiment. We did not find significant differences between the two groups. These findings suggest that physical and motor imagery practice drive skill learning through different acquisition and consolidation processes. [ABSTRACT FROM AUTHOR]

Formic acid is obtained in equimolar amount with levulinic acid during the hydrolysis of cellulose and thus can be used as a sustainable hydrogen source in the direct levulinic acid hydrogenation towards gamma-valerolactone (biofuel additive). Ag Pd catalysts prepared by various methods and containing different Ag:Pd ratio were investigated in this context. By combining activity tests, characterization of the main physicochemical properties of the catalysts and DFT study of formic acid decomposition, the key factors responsible for the activity of Ag Pd catalysts in both the formic acid decomposition and the subsequent hydrogenation of levulinic acid were specified. Pd is shown to be active, but prone to poisoning by CO, while the CO poisoning remains limited on diluted Ag Pd alloy with strong intermetallic interaction, where its adsorption is very weak thanks to the isolation of Pd atoms. Therefore, the catalyst containing 4%Ag-1%Pd/AlOOH showed the highest selectivity in formic acid decomposition as well as the highest activity in levulinic acid hydrogenation (34% conversion in 5 h at 190 °C). • Pd–Ag catalysts are active in the formic acid decomposition and levulinic acid hydrogenation tandem process. • Pd–Ag catalysts are reducing CO poisoning compared to the active Pd counterpart. • Preparation method and Ag:Pd ratio allow to tune the activity of the reaction. • Periodic DFT computations were used to rationalize the activity of Pd–Ag catalysts. [ABSTRACT FROM AUTHOR]

The acceptor‐less dehydrogenation of 2‐octanol was tested over cobalt supported on Al2O3, C, ZnO, ZrO2 and various TiO2 substrates. The catalysts were characterized by ICP, XRD and TGA‐H2. For Co/TiO2 P25, the effects of passivation, aging (storage at room temperature), and in situ activation under H2 were investigated. The catalysts must be tested shortly after synthesis in order to prevent deactivation. Cobalt supported on TiO2 P25 was the most active and 69 % yield of 2‐octanone was obtained, using decane as a solvent. Selectivities for 2‐octanone were observed in the range of 90 % to 99.9 %. Small amounts of C16 compounds were also formed due to aldol condensation/dehydration reactions. The catalysts exhibited higher conversion in the dehydrogenation of secondary alcohols (65‐69 %), in comparison to primary alcohols (2–10 %). The dehydrogenation of 1,2‐octanediol led to 1‐hydroxy‐2‐octanone, with a selectivity of 90 % and 69 % for Co/TiO2 P25 and Co/TiO2 P90, respectively. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Supported metal catalysts convert α-homocitric acid lactone to C6 diacids. • Selected catalysts afford primarily adipic, 2-Et-succinic, or 2-Me-glutaric acid. • Reaction pathway involves dehydration-isom-decarboxylation-hydrogenation relay. • DFT studies identify thermodynamic stabilities of reaction intermediates/products. Abstract Conversion of renewable resources to the chemicals and materials needed for consumer products represents an exciting challenge for catalysis science. Here we discuss our initial progress on synthesizing C6 diacids from the sugar fermentation intermediate α-homo-citric acid lactone using supported heterogeneous catalysts in water. Using high-throughput catalysis testing we have identified several promising catalysts for this process that yield different amounts of the three C6 diacids: adipic, 2-methylglutaric and 2-ethylsuccinic. The process involves a relay of four different chemical reactions: dehydration, alkene isomerization, decarboxylation and alkene hydrogenation. DFT studies have been initiated in order to rationalize the activity and selectivity based on catalyst properties. [ABSTRACT FROM AUTHOR]

Abstract: Among the best‐performing homogeneous catalysts for the direct amination of activated secondary alcohols with electron‐poor amine derivatives, metal triflates, such as aluminum triflate, Al(OTf)3, stand out. Herein we report the extension of this reaction to electron‐rich amines and activated primary alcohols. We provide detailed insight into the structure and reactivity of the catalyst under working conditions in both nitromethane and toluene solvent, through experiment (cyclic voltammetry, conductimetry, NMR spectroscopy), and density functional theory (DFT) simulations. Competition between aniline and benzyl alcohol for Al in the two solvents explains the different reactivities. The catalyst structures predicted from the DFT calculations were validated by the experiments. Whereas a SN1‐type mechanism was found to be active in nitromethane, we propose a SN2 mechanism in toluene to rationalize the much higher selectivity observed when using this solvent. Also, unlike what is commonly assumed in homogeneous catalysis, we show that different active species may be active instead of only one. [ABSTRACT FROM AUTHOR]

The efficiency of direct ethanol fuel cells suffers from the partial oxidation of ethanol into acetic acid as opposed to the complete oxidation of this fuel to CO 2 . Herein, we support the quest for a selective catalyst for ethanol electro-oxidation to CO 2 , building on our previous mechanistic hypothesis based on experimental insight and DFT computations. We derive a simple descriptor of the expected selectivity towards full oxidation, Ω, as a function of the adsorption energy of atomic C and O. Three different families of catalyst surfaces are screened using this descriptor: monometallics, bimetallics and conducting metal oxides, totaling to 600 surfaces. In agreement with available experimental data, no single metal surface is more selective for total oxidation than platinum and palladium. While the selected conducting oxides were not predicted to be selective towards splitting the C C bond, structurally-controlled monometallics (such as Pd(100)) or some bimetallics (Pd 3 Ag) are found to be competitive with the most stable facet, (111), of Pd and Pt. Despite this very extensive screening, no very promising catalyst has been identified. This highlights the need to identify catalysts for acetate oxidation or to exploit support effects and electrolyte engineering to profit from the full power of direct ethanol fuel cells. [ABSTRACT FROM AUTHOR]

We re-investigate the image charge model of Iori and Corni (Iori and Corni, J. Comput. Chem. 2008, 29, 1656). We find that a simple symmetrization of their model allows to obtain quantitatively correct results for the electrostatic interaction of a water molecule with a metallic surface. This symmetrization reduces the magnitude of the electrostatic interaction to less than 10% of the total interaction energy. © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Bulk (Mo 2 N) and supported molybdenum nitride (Mo 2 N/TiO 2 , Mo 2 N/CeO 2) were synthesized by reduction-nitridation of bulk and supported MoO 3 under a mixture of N 2 /H 2. We investigated the mechanism of formation of molybdenum nitrides by coupling elemental analysis, in situ and ex situ XRD, Raman spectroscopy, in situ XPS/UPS spectroscopy and DFT calculation. We showed that it is possible to control the crystallographic phase and degree of nitridation (i.e. nitrogen vacancies) by adjusting the parameters of the synthesis, including the heating rate and final temperature, the nature, composition and flow of gas during reduction/nitridation and cooling. We demonstrated that β-Mo 2 N and γ-Mo 2 N go through the same intermediates: molybdenum bronze, MoO 2 and Mo. The final crystallographic phase of the nitride depends mainly on the temperature rate and gas hourly space velocity employed during the synthesis, as they impact the crystallite size of the intermediates and the kinetics of reduction and nitridation. Molybdenum nitride clusters (<0.5 nm) are formed on TiO 2. [Display omitted] • Mechanism of formation of tetragonal and cubic molybdenum nitride with N 2 /H 2. • Identification of molybdenum bronze (H x MoO 3) as a new intermediate. • Controlling the crystallographic phase and nitrogen content of molybdenum nitride. • In situ X-ray and Ultraviolet photoelectron spectroscopy coupled with DFT calculation. • Synthesis of small clusters (<0.5 nm) of Mo 2 N on TiO 2. [ABSTRACT FROM AUTHOR]

The catalytic hydrogenation of levulinic acid (LA) with formic acid (FA) as a hydrogen source into γ-valerolactone (GVL) is considered as one of the crucial sustainable processes in today's biorefinery schemes. In the current work, we investigated the modification of Ru/C as efficient catalysts for both formic acid decomposition and levulinic acid hydrogenation in comparison with Pd and Pt catalysts. In order to better understand what features are responsible for high catalytic performance, we combined experimental tests, DFT calculations together with extensive material characterization. In LA hydrogenation with FA as a hydrogen source, the intermediate surface formate inhibits at least partially the LA hydrogenation. In addition, the FA decomposition is highly sensitive to the kind of the preparation method of the Ru/C catalyst: (i) the process looks structure sensitive favored on larger particles and (ii) residual chlorine decreases significantly the FA decomposition rate. [ABSTRACT FROM AUTHOR]

Reaction of Fe(NO 3 ) 3 with 3,6-di(pyrimidin-2-yl)-1,2,4,5-tetrazine (BPymTz) in acetonitrile gives a hepta-coordinated Fe III complex ( 1 ) with the bridging unit 1,2-diiminohydrazido (1,2-dih 2− : − HN C(R) N N C(R) NH − ) generated in situ from the tetrazine ring-opening of BPymTz. DFT calculations, X-ray diffraction studies and SQUID magnetometry measurements were successfully performed on 1 . The crystallography measurement confirms the ring-opening and the substituent’s contribution to the rare pentagonal bipyramidal coordination geometry of the metal ions. Magnetic susceptibility measurements on 1 reveal an S = 0 ground state, arising from the antiferromagnetic interaction between the two Fe III centers ( J = −3.02 cm −1 ) within the molecule. [ABSTRACT FROM AUTHOR]

Highlights: [•] Rightward bias for central location in children with dyslexia in line bisection. [•] Asymmetrical effect of line location in children with dyslexia. [•] Lateral effect towards the starting position in proprioceptive circle centering. [•] Forward (backward) effect in visuo-proprioceptive (proprioceptive) circle centering. [•] Influence of the left starting position in radial response in children with dyslexia. [Copyright &y& Elsevier]

Significant yields of lactic acid (LA) are obtained during the treatment of glycerol solution under inert gas with supported metallic catalysts under basic conditions. The nature of the atmosphere and the metal affected the activity and the selectivity of the reaction. Iridium-based catalysts are efficient for LA synthesis. [ABSTRACT FROM AUTHOR]

We show how the combination of Bias Exchange metadynamics (BE) with Car-Parrinello molecular dynamics (CPMD) can lead to vast improvements in the study of chemical reactions. Bias Exchange metadynamics is a recently introduced methodology that combines replica exchange techniques with the metadynamics approach. It allows fast parallel reconstruction of the free energy of a system in a virtually unlimited number of variables. The value of the method was previously demonstrated for the folding of a Triptophane cage miniprotein on the classical potential energy surface. As a test case for the DFT implementation, we investigated the competitive SN2 reaction of CH3Cl with Cl- and Br-. The results illustrate three important advantages of the method. (1) Fast and complete sampling of configuration space occurs in each replica. (2) A significant speed-up can be observed in the convergence of the free energy profiles, compared with regular metadynamics. (3) The best conformational distributions are successfully transferred from one replica to the others. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [ABSTRACT FROM AUTHOR]

Abstract: An improved version of our method for computing QTAIM [J.I. Rodríguez, A.M. Köster, P.W. Ayers, A. Santos-Valle, A. Vela, G. Merino, J. Comput. Chem. (2009), in press, doi:10.1002/jcc.21134] is presented. Vectorization and parallelization of the previous algorithm, together with molecular symmetry, make the present algorithm as much as two orders of magnitude faster than our original method. The present method scales linearly with both system size and the number of processors. The performance of the method is demonstrated by computing the QTAIM atomic properties of a series of carbon nanotubes. Our results show that the CPU time for a QTAIM property calculation is comparable to that of a SCF-single point calculation. The accuracy of the original method is also improved. [Copyright &y& Elsevier]

Prism adaptation consists of pointing to visual targets while wearing prisms that shift the visual field laterally. The aftereffects are not restricted to sensorimotor level but extend to spatial cognition. There is a link between spatial representation and auditory frequency, with an association of low frequencies on the left side and high frequencies on the right side of space. The present study aimed first at evaluating the representation of auditory frequencies on a wide range of frequencies in musicians and nonmusicians. We used the 'auditory interval bisection judgment' within three auditory intervals. The results showed a pseudoneglect behavior in pretest in musicians and nonmusicians for high frequency intervals, reflecting a perceptual bias of the subjective interval center toward lower frequencies. The second aim of the present study was to evaluate the aftereffects of prism adaptation on an expanded auditory spectrum. The results showed aftereffects of adaptation to a leftward optical deviation for high frequency intervals in musicians and nonmusicians. Adaptation to a leftward optical deviation affects the auditory perception on an extended auditory spectrum, by shifting the subjective interval center toward high frequencies. The present study provides innovative data about representation of auditory perception and its modulation by prism adaptation. • Pseudoneglect exists in the auditory frequency representation. • Prism adaptation affects the representation of higher frequencies. • Pseudoneglect and prism adaptation aftereffects are independent of musical expertise. [ABSTRACT FROM AUTHOR]