相关论文: On chemical bonding of Helium with hcp-Beryllium
The crystal structure, mechanical properties and electronic structure of ground state BeH$_{2}$ are calculated employing the first-principles methods based on the density functional theory. Our calculated structural parameters at…
Helium (He) is the most inert noble gas at ambient conditions. It adopts a hexagonal close packed structure (P63/mmc) and remains in the insulating phase up to 32 TPa. In contrast, lithium (Li) is one of the most reactive metals at zero…
Helium is generally understood to be chemically inert and this is due to its extremely stable closed-shell electronic configuration, zero electron affinity and an unsurpassed ionization potential. It is not known to form thermodynamically…
Particle yields in heavy ion collisions show an overwhelming evidence for chemical or relative chemical equilibrium at all beam energies. The rapidity dependence of the thermal parameters $T$ and $\mu_B$ can now be determined over a wide…
The long range interaction between an antiprotonic helium atom $\bar{p}$He$^+$ and helium atom in its ground state is studied. We calculate the dispersion coefficients $C_6$ using the Complex Coordinate Rotation (CCR) formalism in order to…
Chemical bonding is the stabilization of a composite molecular system caused by different interactions in and between the subsystems, among the strong kinds of bonding is covalent bonding especially important. Characteristic for covalent…
The polymorphism and mechanism of helium compounds is crucial for understanding the physical and chemical nature of He-bearing materials under pressures. Here, we predict two new types of He-bearing compounds, MgHe and MgnHe (n = 6, 8, 10,…
Density-functional theory calculations based on conventional as well as hybrid exchange-correlation functionals have been carried out to study the properties of helium in various oxides (Al2O3, TiO2, Y2O3, YAP, YAG, YAM, MgO, CaO, BaO, SrO)…
The solubility of helium in liquid metals is a knowledge of fundamental importance in the design of the future nuclear fusion reactors, since the formation of helium bubbles inside the breeding blankets of the reactors can be a threat to…
The present study explores electronic and structural properties, ionization potential (IP), electron affinity (EA), polarizability ({\alpha}), chemical potential (\mu), hardness ({\eta}), softness (S), band gap ({\Delta}E(HOMO-LUMO)) and…
The extremely low solubility of helium in liquid metals may lead to rapid supersaturation, promoting spontaneous formation of helium bubbles by nucleation. Once nucleated, the stability of these bubbles is governed by the properties of the…
Equilibrium properties of hydrogen-helium mixtures under thermodynamic conditions found in the interior of giant gas planets are studied by means of density functional theory molecular dynamics simulations. Special emphasis is placed on the…
Our first-principles density functional theory calculations suggest that the rare earth element, Ce, has a stronger attraction (-1.31eV) to He than He-He (-1.18eV) in bcc Fe. Consequently, the mobile He atoms could be pinned to Ce, and…
Understanding helium accumulation in plasma-facing or structural materials in a fusion reactor starts from uncovering the details of the migration of single and paired He interstitials. We have carried out a first-principles density…
The centrality dependence of thermal parameters, characterizing the hadron multiplicities, is determined phenomenologically for lead-on-lead collisions at CERN-SPS for a beam energy of 158 AGeV. The strangeness equilibration factor shows a…
We investigate the binary phase diagram of helium and iron using first-principles calculations. We find that helium, which is a noble gas and inert at ambient conditions, forms stable crystalline compounds with iron at terapascal pressures.…
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…
The way atoms attach to each other defines the function(s), e.g., mechanical, optical, electronic, of a given material. The nature of the chemical bond is, therefore, one of the most fundamental issues in materials. Both ionic interactions,…
Polarizabilities, dispersion coefficients, and long-range atom-surface interaction potentials are calculated for the n=2 triplet and singlet states of helium using highly accurate, variationally determined, wave functions.
Hydrogen, helium, silicates, and iron are key building blocks of rocky and gas-rich planets, yet their chemical interactions remain poorly constrained. Using first-principles molecular dynamics and thermodynamic integration, we quantify…