Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
First principles calculations, employed to address the properties of polycrystalline graphene, indicate that the electronic structure of tilt grain boundaries in this system displays a rather complex evolution toward graphene bulk, as the tilt angle decreases, with the generation of a Dirac point, at the Fermi level,…
We examine theoretically the effects of random topographical substrates on the motion of two-dimensional droplets via statistical approaches, by representing substrate families as stationary random functions. The droplet shift variance at both early times and in the long-time limit is deduced and the droplet footprint…
The gap generation is studied in suspended clean graphene in the continuum model for quasiparticles with the Coulomb interaction. We solve the gap equation with the dynamical polarization function and show that, comparing to the case of the static polarization function, the critical coupling constant lowers to the val…
Understanding of the physical characteristics of a polymer requires molar mass determination. For the commercially available polymers, having average molar mass below 1 000 000 g/mol, chromatography is the method that is often applied to determine the molar mass and molar mass distribution. However, the application of…
The structures, cohesive energies, and highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gaps of graphene nanoflakes and corresponding polycyclic aromatic hydrocarbons for a large variety of size and topology are investigated at the density-functional-based tight-binding level. Polya…
The thermal conductivity of a nanostructure is sensitive to its dimensions. A simple analytical scaling law that predicts how conductivity changes with the dimensions of the structure, however, has not been developed. The lack of such a law is a hurdle in ``phonon engineering'' of many important applications. Here, we…
We propose a different class of materials, which can be viewed as graphene derivatives involving Group IA or Group VIIA elements, forming what we refer to as graphXene. We show that in several cases, large band gaps can be found to open up whereas in other cases, a semimetallic behavior is found. Formation energies in…
Motivated by a suggestion in our earlier work [G. Baskaran, Phys. Rev. B 65, 212505 (2002)], we study electron correlation driven superconductivity in doped graphene where on-site correlations are believed to be of intermediate strength. Using an extensive variational Monte Carlo study of the repulsive Hubbard model a…
In an assembly of double-layered metallic U-shaped resonators with two resonant frequencies ${\ensuremath{\omega}}_{H}$ and ${\ensuremath{\omega}}_{L}$, the effective induced electric and magnetic dipoles, which originate from the specific distribution of induced surface electric current upon the illumination of incid…
High resolution neutron diffraction shows that the mesoscopic separation into ferromagnetic (FM) and antiferromagnetic (AFM) phases and the FM transition temperature T(C) in the perovskite manganite (La(1-y)Pr(y))(0.7)Ca(0.3)MnO(3) strongly depend on the quenched correlated disorder. The different disorder strengths a…
Atomic-sized lead (Pb) contacts are deposited and dissolved in an electrochemical environment, and their transport properties are measured. Due to the electrochemical fabrication process, we obtain mechanically unstrained contacts and conductance histograms with sharply resolved, individual peaks. Charge transport cal…
We use density functional theory based first-principles methods to study the magnetism in a 2D hexagonal BN sheet induced by the different concentrations of oxygen and silicon atoms substituting for nitrogen (O$_\mathrm{N}$) and boron (Si$_\mathrm{B}$) respectively. We demonstrate the possible formation of three disti…
Electronic and magnetic properties of VnBzn+1 sandwich clusters are investigated using density functional theory. Growth model is applied to investigate the property change of Vanadium-Benzene sandwich clusters. Our results show that, for n<8, all V ions tend to put their spin in ferromagnetic state, and that the magn…
The properties of organometallic wires [TM2(Ant)] constructed with transitional metals (TM = Sc, Ti, V, Cr, Mn and Fe) and anthracene (Ant) are investigated by first-principles calculations. As the gap between HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular Orbital) of Ant is much small…
Using density-functional theory within the generalized gradient approximation, we investigate the interaction between atomic oxygen and Cu(100) and Cu(110) surfaces. We consider the adsorption of oxygen at various on-surface and subsurface sites of Cu(100) for coverages of 1/8 to 1 monolayers (ML). We find that oxygen…
Armor‐grade B 4 C and SiC specimens were analyzed for phase assemblage, microstructure, and mechanical properties. SiC–N showed the highest four‐point fracture strength, and an ∼50% higher notched beam fracture toughness than solid‐state sintered B 4 C and SiC. This was attributed to preferential crack propagation alo…
Chitosan is a polysaccharide formed mainly from repeating residues of D-glucosamine, having primary amino groups. It is of great interest not only as an underutilized resource, but also as a new functional material of high potential in various fields, and recent progress in chitin chemistry is quite noteworthy. The pu…
We show that Clar's theory of the aromatic sextet is a simple and powerful tool to predict the stability, the pi-electron distribution, the geometry, and the electronic/magnetic structure of graphene nanoribbons with different hydrogen edge terminations. We use density functional theory to obtain the equilibrium atomi…
We use density functional theory (DFT) with a recently developed van der Waals density functional (vdW-DF) to study the adsorption of graphene on Co, Ni, Pd, Ag, Au, Cu, Pt, and Al(111) surfaces. In contrast to the local-density approximation (LDA) which predicts relatively strong binding for Ni,Co, and Pd, the vdW-DF…
Polymer networks possessing reversible covalent crosslinks constitute a novel material class with the capacity for adapting to an externally applied stimulus. These covalent adaptable networks (CANs) represent a trend in polymer network fabrication towards the rational design of structural materials possessing dynamic…