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Electroactive organic compounds could bring new chemical opportunities to further improve existing electrochemical energy‐storage technologies as they can be prepared from less‐limited resources and potentially at low environmental footprint. Among the current explored research fields, the anion–ion cell configuration appears poorly investigated although quite promising to promote the fabrication of molecular (metal‐free) rechargeable batteries. Herein, we report the synthesis and the electrochemical behavior of both Mg/Li salts of 2,5‐(dianilino)terephthalate (MgDAnT and Li2DAnT) and cross‐linked polyviologen (c‐PV2+) that can reversibly uptake/extract anions at different working potentials, enabling the assembly of full anionic organic batteries. The reversible anion ingress in MgDAnT is however accompanied by solvent co‐insertion from the electrolyte that provokes an overpotential effect during the first charge. Full anionic batteries pairing Li2DAnT with c‐PV2+ were assembled giving rise to 0.7 V as output voltage with a specific capacity of 50 mAh per gram of Li2DAnT. [ABSTRACT FROM AUTHOR]

Silicon nanoparticles (NPs) serve a wide range of optical, electronic, and biological applications. Chemical grafting of various molecules to Si NPs can help to passivate their reactive surfaces, 'fine-tune' their properties, or even give them further interesting features. In this work, 1H, 13C, and 29Si solid-state NMR spectroscopy has been combined with density functional theory calculations to study the surface chemistry of hydride-terminated and alkyl-functionalized Si NPs. This combination of techniques yields assignments for the observed chemical shifts, including the contributions resulting from different surface planes, and highlights the presence of physisorbed water. Resonances from near-surface 13C nuclei were shown to be substantially broadened due to surface disorder and it is demonstrated that in an ambient environment hydride-terminated Si NPs undergo fast back-bond oxidation, whereas long-chain alkyl-functionalized Si NPs undergo slow oxidation. Furthermore, the combination of NMR spectroscopy and DFT calculations showed that the employed hydrosilylation reaction involves anti-Markovnikov addition of the 1-alkene to the surface of the Si NPs. [ABSTRACT FROM AUTHOR]

The preparation and characterization of a series of complexes of the Yb and Eu cations in the oxidation state II and III with the tetradentate N,O-donor tripodal ligands (tris(2-pyridylmethyl)amine (TPA), BPA− (HBPA=bis(2-pyridylmethyl)(2-hydroxybenzyl)amine), BPPA− (HBPPA=bis(2-pyridylmethyl)(3.5-di- tert-butyl-2-hydroxybenzyl)amine), and MPA2− (H2MPA=(2-pyridylmethyl)bis(3.5-di- tert-butyl-2-hydroxybenzyl)amine) is reported. The X-ray crystal structures of the heteroleptic Ln2+ complexes [Ln(TPA)I2] (Ln=Eu, Yb) and [Yb(BPA)I(CH3CN)]2, of the Ln2+ homoleptic [Ln(TPA)2]I2 (Ln=Sm, Eu, Yb) and [Eu(BPA)2] complexes, and of the Ln3+ [Eu(BPPA)2]OTf and [Yb(MPA)2K(dme)2] (dme=dimethoxyethane) complexes have been determined. Cyclic voltammetry studies carried out on the bis-ligand complexes of Eu3+ and Yb3+ show that the metal center reduction occurs at significantly lower potentials for the BPA− ligand as compared with the TPA ligand. This suggests that the more electron-rich character of the BPA− ligand results in a higher reducing character of the lanthanide complexes of BPA− compared with those of TPA. The important differences in the stability and reactivity of the investigated complexes are probably due to the observed difference in redox potential. Preliminary reactivity studies show that whereas the bis-TPA complexes of Eu2+ and Yb2+ do not show any reactivity with heteroallenes, the [Eu(BPA)2] complex reduces CS2 to afford the first example of a lanthanide trithiocarbonate complex. [ABSTRACT FROM AUTHOR]

Magic-angle spinning dynamic nuclear polarization (MAS-DNP) has been proven to be a powerful technique to enhance the sensitivity of solid-state NMR (SSNMR) in a wide range of systems. Here, we show that DNP can be used to polarize lipids using a lipid-anchored polarizing agent. More specifically, we introduce a C16-functionalized biradical, which allows localization of the polarizing agents in the lipid bilayer and DNP experiments to be performed in the absence of excess cryo-protectant molecules (glycerol, dimethyl sulfoxide, etc.). This constitutes another original example of the matrix-free DNP approach that we recently introduced. [ABSTRACT FROM AUTHOR]

Summary: In High Performance Computing, heterogeneity is now the norm with specialized accelerators like GPUs providing efficient computational power. Resulting complexity led to the development of task‐based runtime systems, where complex computations are described as task graphs, and scheduling decisions are made at runtime to perform load balancing between all the resources of the platforms. Developing good scheduling strategies, even at the scale of a single node, and analyzing them both theoretically and in practice are expected to have a very high impact on the performance of current HPC systems. The special case of 2 kinds of resources, typically CPUs and GPUs, is already of great practical interest. The scheduling policy HeteroPrio has been proposed in the context of fast multipole computations (FMM) and has been extended to general task graphs with very promising results. In this paper, we provide a theoretical study of the performance of HeteroPrio, by proving approximation bounds compared to the optimal schedule, both in the case of independent tasks and in the case of general task graphs. Interestingly, our results establish that spoliation (a technique that enables resources to restart uncompleted tasks on another resource) is enough to prove bounded approximation ratios for a list scheduling algorithm on two unrelated resources, which is known to be impossible otherwise. This result holds true both for the independent and dependent tasks graphs. Additionally, we provide an experimental evaluation of HeteroPrio on real task graphs from dense linear algebra computation, which establishes its strong performance in practice. [ABSTRACT FROM AUTHOR]

A new series of complexes of Eu2+ and Yb2+ with tripodal aminophenolate ligands are reported by M. Mazzanti and colleagues in their Full Paper on page 15188 ff. Cyclic voltammetry studies show that these ligands can be effectively used to tune the redox properties and reactivity of lanthanide ions possessing weak reducing power. The increased reducing power of Eu2+ in a homoleptic aminophenolate complex allows the reduction of CS2 and affords the first example of a lanthanide trithiocarbonate complex. [ABSTRACT FROM AUTHOR]

Matrix ‐ Free DNP on Lipid Membranes Dynamic nuclear polarization (DNP) has been proven to be a powerful technique to enhance the sensitivity of solid ‐ state NMR. However, until now, there has been limited success in its application to synthetic membrane ‐ type systems. In their Communication on page 4512 ff., G. De Paëpe et al. present an innovative approach based on system ‐ driven radical design in order to insert the polarizing agent inside a lipid bilayer. Combined with matrix ‐ free DNP, this strategy solves additive ‐ induced problems by releasing the need for a DNP ‐ compatible solvent. [ABSTRACT FROM AUTHOR]