相关论文: Carbon Vacancy Formation in Binary Transition Meta…

The discovery of nearly room-temperature superconductivity in superhydrides has motivated further materials research for conventional superconductors. To realize the moderately high critical temperature $(T_\mathrm{c})$ in materials…

Most elemental metals under ambient conditions adopt simple structures such as BCC, FCC and HCP in specific groupings across the Periodic Table, and on compression, many of these elements undergo transitions to surprisingly complex…

It is well known that pressure causes profound changes in the properties of atoms and chemical bonding, leading to the formation of many unusual materials. Here we systematically explore all stable calcium carbides at pressures from ambient…

Using the density functional tight binding method (DFTB) and the GFN1-xTB (Geometries, Frequencies, and Noncovalent interactions Tight Binding) Hamiltonian, we have investigated the structural, electronic and magnetic properties of vacancy…

The development of super-hard materials has recently focused on systems containing a heavy transition metal and light main group elements. Niobium carbides and nitrides have previously been identified as potential candidates, however, the…

The origin of transition metal vacancies and their effects on the properties of ThCr2Si2-type compounds have been less studied and poorly understood. Here we carefully investigate the structure, physical properties, and electronic structure…

Cubic rocksalt structured transition-metal carbides, nitrides, and related alloys (TMC/Ns) are attractive for a wide variety of applications, notably as hard, wear-resistant material. To-date, valence electron concentration (VEC) is used as…

A density functional theory study of atomic defects and dopants in ternary Z-phase transition-metal nitrides CrMN with M=V, Nb, or Ta is presented. Various defect formation energies of native point defects and of substitutional atoms of…

The structural, electronic, and magnetic properties of pristine, defective, and oxidized monolayer TiS3 are investigated using first-principles calculations in the framework of density functional theory. We found that a single layer of TiS3…

Hydrogen is playing a crucial role in the green energy transition. Yet, its tendency to react with and diffuse into surrounding materials poses a challenge. Therefore, it is critical to develop coatings that protect hydrogen-sensitive…

Using first-principles methods we performed a theoretical study of carbon clusters in silicon carbide nanowires. We examined small clusters with carbon interstitials and antisites in hydrogen-passivated SiC nanowires growth along the [100]…

Recent observations indicate potentially carbon-rich exoplanet atmospheres. Spectral fitting methods for brown dwarfs and exoplanets have invoked the C/O ratio as additional parameter but carbon-rich cloud formation modeling is a challenge…

Dwarf carbon (dC) stars, main sequence stars showing carbon molecular bands, are enriched by mass transfer from a previous asymptotic-giant-branch (AGB) companion, which has since evolved to a white dwarf. While previous studies have found…

Using an ab initio approach, we explore the stability of small vacancy and vacancy-chromium clusters in dilute body-centred cubic Fe-Cr alloys. To explain experimental observations described in C.D. Hardie et al., J. Nucl. Mater. 439, 33…

In this work, we have systematically studied structural, electronic and magnetic properties of atomic scale defects in 2D transition metal dichalcogenides MX$_2$, (M = Mo and W; X = S, Se and Te) by density functional theory. Various types…

Adsorption and catalytic properties of the polar (111) surface of transition-metal carbides (TMC's) are investigated by density-functional theory. Atomic and molecular adsorption are rationalized with the concerted-coupling model, in which…

Boron Carbide exhibits a broad composition range, implying a degree of intrinsic substitutional disorder. While the observed phase has rhombohedral symmetry (space group R3(bar)m), the enthalpy minimizing structure has lower, monoclinic,…

There is a direct relation between the composition of a host star and that of the planets orbiting around it. As such, the recent discovery of stars with unusual chemical composition, notably enriched in carbon instead of oxygen, support…

Energy band structures of metal-deficient hexagonal diborides M$_{0.75}$B$_2$ (M = Nb, Zr and Y) were calculated using the full-potential LMTO method. The metal vacancies change the density of states near the Fermi level and this effect is…

High entropy metal nitrides are an important material class in a variety of applications, and the role of nitrogen vacancies is of great importance for understanding their stability and mechanical properties. We study six different high…