Fowlerwren7782

Machine learning techniques have been used to quantify the relationship between local structural features and variations in local dynamical activity in disordered glass-forming materials. To date these methods have been applied to an array of standard (Arrhenius and super-Arrhenius) glass formers, where work on "soft spots" indicates a connection between the linear vibrational response of a configuration and the energy barriers to non-linear deformations. Here we study the Voronoi model, which takes its inspiration from dense epithelial monolayers and which displays anomalous, sub-Arrhenius scaling of its dynamical relaxation time with decreasing temperature. Despite these differences, we find that the likelihood of rearrangements can nevertheless vary by several orders of magnitude within the model tissue and extract a local structural quantity, "softness," that accurately predicts the temperature dependence of the relaxation time. We use an information-theoretic measure to quantify the extent to which softness determines impending topological rearrangements; we find that softness captures nearly all of the information about rearrangements that is obtainable from structure, and that this information is large in the solid phase of the model and decreases rapidly as state variables are varied into the fluid phase.In comparison with the prevalent 2D material-supported single atom catalysts (SACs), the design and fabrication of SACs with single molecule substrates are still challenging. Here we introduce a new type of SAC in which a recently identified all-boron fullerene B40 is employed as the support and its catalytic performance toward the nitrogen reduction reaction (NRR) process is explored in theory. Taking advantage of the novel heptagonal ring substructure on the sphere and the electron-deficient nature of boron, the atomic metals are facile to reside on B40 to form atomically dispersed η7-B40M exohedral complexes. Among a series of candidates, originating from the proper metal-adsorbate interactions, the atomic tungsten-decorated B40W is screened out as the most feasible catalyst for the NRR with a low over-potential and high selectivity to passivate the competitive hydrogen evolution process.Two-dimensional (2D) materials have attracted great interest in the field of optoelectronics in recent years due to their atomically thin structure and various electronic properties. Based on the first-principles calculations combined with the non-equilibrium Green's function (NEGF) method, we predict a set of new 2D ternary materials, sodium copper chalcogenides (NaCuX, X = S, Se, and Te). These materials not only have direct band gaps ranging from 1.2 to 1.6 eV, but also possess relatively small carrier effective masses (0.1-0.2m0) at the band edges thus high carrier mobilities (103-104 cm2 V-1 s-1), which collectively imply that they are suitable for optical-electronic applications in the visible (even in the infrared) light region. Moreover, based on the high photo responsivity (Rph), e.g., up to 0.105 A W-1 for NaCuTe, we design a series of NaCuX monolayer based high performance optoelectronic junctions. These properties indicate that NaCuX monolayers are promising candidate materials for photodetectors and photovoltaic units.Herein, we have unravelled the key influence of aromatic interactions on the mechanistic pathways of peptide self-assembly by introducing suitable chromophores (pyrene vs. naphthalene). Although both self-assembled peptides are indistinguishable in their morphologies, this minor structural difference strongly affects the packing modes (parallel vs. antiparallel) and the corresponding self-assembly mechanism (cooperative vs. isodemsic).We report a crystalline supramolecular framework assembled by H-bonding interactions between covalently fused monomers equipped with two guanine-cytosine nucleobase pairs.Prussian blue analogues are potential competitive energy storage materials due to their diverse metal combinations and wide three-dimensional ion channels. Here, we prepared a new highly crystalline monoclinic nickel-doped cobalt hexacyanoferrate via a feasible and simple one-step co-precipitation method. In the process of sodium-ion de-intercalation, three stable charge and discharge platforms, which are consistent with the cyclic voltammetry performance, are seen for the first time, showing the function of nickel ions in Prussian blue. Furthermore, the charge transfer and structural evolution caused by the transmission of sodium ions were well revealed via ex situ XRD, ex situ XPS, and in situ EIS studies. Simulation calculations are performed relating to the energy band structure and the highest-occupied bonding orbitals of the system in different charge states, revealing the charge and discharge mechanism of the nickel-doped material and the reason for the emergence of the new platform at low voltages. In addition, NaNi0.17Co0.83Fe(CN)6 also delivers a striking capacity of 146 mA h g-1 and superior cyclability, with 93% capacity retention over 100 cycles; it can be considered as a promising alternative cathode material for use in sodium-ion batteries.ortho-Silylaryl triflate precursors (oSATs) have been responsible for many recent advances in aryne chemistry and are most commonly accessed from the corresponding 2-bromophenol. find more A retro-Brook O- to C-silyl transfer is a key step in this synthesis but not all aromatic species are amenable to the transformation, with no functionalized bisbenzyne oSATs reported. Simple Hückel models are presented which show that the calculated aromaticity at the brominated position is an accurate predictor of successful retro-Brook reaction, validated synthetically by a new success and a predicted failure. From this, the synthesis of a novel difunctionalized bisaryne precursor has been tested, requiring different approaches to install the two C-silyl groups. The first successful use of a disubstituted o-silylaryl sulfonate bisbenzyne precursor in Diels-Alder reactions is then shown.We report the direct observation of the formation and degradation of tensegrity triangle DNA crystals using atomic force microscopy (AFM). We observed the crystal surface by AFM and characterized the lattice coordination of the assembled triangle units at a molecular level. We visualized dynamic formation and degradation of the crystals and characterized them at nano-scale resolution.