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The locally heterogeneous dynamics of the glass‐forming liquids is an unusual and distinct phenomenon that is not observed in a typical liquid system above the melting temperature. Room‐temperature ionic liquids (RTILs) are usually good glass formers, exhibiting various interesting features of glassy materials such as nonexponential and non‐Arrenhius relaxations and transport decoupling behaviors. In this study, we propose a minimal model that represents the general structural features of RTILs to study their dynamics by extending the restricted primitive model. We mainly focus on the heterogeneous dynamics of the RTIL as a glass former and investigate how the charge symmetry of each ion affects the structural relaxation, diffusive behavior, and the dynamic heterogeneity lifetime of the system. [ABSTRACT FROM AUTHOR]

Herein, the self‐reinforced inductive effect derived from coexistence of both p‐ and n‐type redox‐active motifs in a single organic molecule is presented. Molecular orbital energy levels of each motif are dramatically tuned, which leads to the higher oxidation and the lower reduction potentials. The self‐reinforced inductive effect of the symmetric bipolar organic molecule, N,N'‐dimethylquinacridone (DMQA), is corroborated, by both experimental and theoretical methods. Furthermore, its redox mechanism and reaction pathway in the Li+‐battery system are scrutinized. DMQA shows excellent capacity retention at the operating voltage of 3.85 and 2.09 V (vs Li+/Li) when used as the cathode and anode, respectively. Successful operation of DMQA electrodes in a symmetric all‐organic battery is also demonstrated. The comprehensive insight into the energy storage capability of the symmetric bipolar organic molecule and its self‐reinforced inductive effect is provided. Thus, a new class of organic electrode materials for symmetric all‐organic batteries as well as conventional rechargeable batteries can be conceived. [ABSTRACT FROM AUTHOR]

A stochastic lineshape theory is formulated for the non-Markovian and multistate frequency modulation model. The frequency of the stochastic oscillator undergoes non-Markovian modulations between multiple states, and the transition processes are described by arbitrary waiting-time distributions. By incorporating stationarity into the stochastic process in a proper way, we calculate the propagator and the relaxation function. It is shown that a stationary distribution among the oscillator states satisfies a generalized detailed balance condition even in the non-Markovian case. We find an exact expression for the lineshape function, which contains the Markovian case as a special limit. [ABSTRACT FROM AUTHOR]

The nature of hydrated protons formed at water/metal interfaces is one of the most intriguing research questions in the field of interfacial chemistry. We prepared coadsorption layers of hydrogen and water on a Pt(111) surface in ultrahigh vacuum and studied the ionization of adsorbed hydrogen atoms to H+ ions by employing a combined experimental and theoretical approach. Spectroscopic evidence obtained by mass spectrometry and reflection absorption infrared spectroscopy as well as corresponding density functional theory calculations consistently show that adsorbed hydrogen atoms ionize into multiply hydrated proton species (H5O2+, H7O3+, and H9O4+) on the surface, rather than H3O+. Then, upon addition of a water overlayer, the metal-bound hydrated protons spontaneously evolve into three-dimensional fully hydrated proton structures through proton transfer along the water overlayer. The stability of hydrated protons on the Pt surface and their bulk dissolution behavior suggest the possibility that surface hydrated protons are a key intermediate in electrochemical interconversion between adsorbed H atoms and H+(aq) in water electrolysis and hydrogen evolution reactions. [ABSTRACT FROM AUTHOR]

Diffusion of long ring polymers in a melt is much slower than the reorganization of their internal structures. While direct evidence for entanglements has not been observed in the long ring polymers unlike linear polymer melts, threading between the rings is suspected to be the main reason for slowing down of ring polymer diffusion. It is, however, difficult to define the threading configuration between two rings because the rings have no chain end. In this work, evidence for threading dynamics of ring polymers is presented by using molecular dynamics simulation and applying a novel analysis method. The simulation results are analyzed in terms of the statistics of persistence and exchange times that have proved useful in studying heterogeneous dynamics of glassy systems. It is found that the threading time of ring polymer melts increases more rapidly with the degree of polymerization than that of linear polymer melts. This indicates that threaded ring polymers cannot diffuse until an unthreading event occurs, which results in the slowing down of ring polymer diffusion. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide (NAD+) is one of the most well‐known redox cofactors carrying electrons. Now, it is reported that the intrinsically charged NAD+ motif can serve as an active electrode in electrochemical lithium cells. By anchoring the NAD+ motif by the anion incorporation, redox activity of the NAD+ is successfully implemented in conventional batteries, exhibiting the average voltage of 2.3 V. The operating voltage and capacity are tunable by altering the anchoring anion species without modifying the redox center itself. This work not only demonstrates the redox capability of NAD+, but also suggests that anchoring the charged molecules with anion incorporation is a viable new approach to exploit various charged biological cofactors in rechargeable battery systems. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide (NAD+) is one of the most well‐known redox cofactors carrying electrons. Now, it is reported that the intrinsically charged NAD+ motif can serve as an active electrode in electrochemical lithium cells. By anchoring the NAD+ motif by the anion incorporation, redox activity of the NAD+ is successfully implemented in conventional batteries, exhibiting the average voltage of 2.3 V. The operating voltage and capacity are tunable by altering the anchoring anion species without modifying the redox center itself. This work not only demonstrates the redox capability of NAD+, but also suggests that anchoring the charged molecules with anion incorporation is a viable new approach to exploit various charged biological cofactors in rechargeable battery systems. [ABSTRACT FROM AUTHOR]

Frontispiz: Biological Nicotinamide Cofactor as a Redox-Active Motif for Reversible Electrochemical Energy Storage Keywords: Bioenergetik; Cofaktoren; Energiespeicherung; Organische Elektroden; Redoxchemie B Energiespeicherung b Das biologisch aktive Nicotinamid-Adenin-Dinukleotid-Motiv ermöglicht eine reversible Energiespeicherung in Lithiumionenbatterien, wie C. B. Park, K. Kang et al. in ihrer Zuschrift auf S. 16920 zeigen. [Extracted from the article]