The experimental investigation of intermolecular charge transport in π‐conjugated materials is challenging. Herein, we describe the investigation of charge transport through intermolecular and intramolecular paths in single‐molecule and single‐stacking thiophene junctions by the mechanically controllable break junction (MCBJ) technique. We found that the ability for intermolecular charge transport through different single‐stacking junctions was approximately independent of the molecular structure, which contrasts with the strong length dependence of conductance in single‐molecule junctions with the same building blocks, and the dominant charge‐transport path of molecules with two anchors transited from an intramolecular to an intermolecular path when the degree of conjugation increased. An increase in conjugation further led to higher binding probability owing to the variation in binding energies, as supported by DFT calculations.

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A lightweight (5.06 g.cm-3) AlTiVCr compositionally complex alloy consisting of four elements is presented. Interest in the system is due to its microstructural uniformity and the use of commodity elements. The focus of the present work was to highlight the systematic microstructural and chemical characterizationand the information gained by application of various physical and modeling techniques in concertin the context of complete characterization of compositionally complex alloys. Herein, analysis of as-cast AlTiVCr was investigated via conventional and scanning transmission electron microscopy, revealing a simple, single-phase microstructure. Characterization was supported by atom probe tomography and X-ray diffraction, whilst first-principles calculations based on density functional theory (DFT) were employed to calculate the thermodynamic and structural properties of the AlTiVCr alloy. The study was able to reveal the unique atomic locations in the alloy, whilst revealing that the B2 phase has a lower formation enthalpy (-9.30 kJ/mol atom) and is more stable than the disordered BCC phase (-1.25 kJ/mol atom) at low temperatures. The study herein provides insight into the combined analysis methods as relevant to the study of compositionally complex and high entropy alloys, indicating means of unambiguous characterization employing generalized multicomponent short range order analysis.

Silicene, analogous to graphene, is a one-atom-thick 2D crystal of silicon, which is expected to share many of the remarkable properties of graphene. The buckled honeycomb structure of silicene, along with enhanced spin-orbit coupling, endows silicene with considerable advantages over graphene in that the spin-split states in silicene are tunable with external fields. Although the low-energy Dirac cone states lie at the heart of all novel quantum phenomena in a pristine sheet of silicene, a hotly debated question is whether these key states can survive when silicene is grown or supported on a substrate. Here we report our direct observation of Dirac cones in monolayer silicene grown on a Ag(111) substrate. By performing angle-resolved photoemission measurements on silicene(3 × 3)/Ag(111), we reveal the presence of six pairs of Dirac cones located on the edges of the first Brillouin zone of Ag(111), which is in sharp contrast to the expected six Dirac cones centered at the K points of the primary silicene(1 × 1) Brillouin zone. Our analysis shows clearly that the unusual Dirac cone structure we have observed is not tied to pristine silicene alone but originates from the combined effects of silicene(3 × 3) and the Ag(111) substrate. Our study thus identifies the case of a unique type of Dirac cone generated through the interaction of two different constituents. The observation of Dirac cones in silicene/Ag(111) opens a unique materials platform for investigating unusual quantum phenomena and for applications based on 2D silicon systems.S ilicene is theoretically predicted to be stable in the honeycomb lattice and, like its cousin graphene, it harbors the characteristic low-energy Dirac cone states (1-6). Silicene can thus be expected to share many of the remarkable quantum properties of graphene (7-10). Distinct from graphene, however, which is dominated by sp 2 bonding and assumes an essentially flat structure, the crystal structure of silicene is naturally buckled as a result of the mixed sp 2 /sp 3 bonding (2-5). The stronger spinorbit coupling strength in silicene (11, 12) leads to a larger energy gap at the Dirac points, which would make it possible to access the quantum spin Hall effect experimentally at a higher temperature (11, 12). The buckled honeycomb structure drives a number of new phenomena and properties in silicene. In particular, the gap at the Dirac point can be tuned by applying external electric and magnetic fields to realize a variety of different phases and topological phase transitions (13-17). The unique advantages of silicene and its compatibility with the traditional silicon industry make it an attractive materials platform for next-generation nanoelectronics applications (18-23).Single-layer and multilayer silicenes have been grown on various supporting materials, with the Ag(111) surface being the most common substrate (24-30). The buckled structure of silicene naturally leads to the formation of a variety of configurations beyond the primary (1 × 1) structure under different preparatio...