相关论文: Ab initio investigations of point and complex defe…
Ab initio calculation results for the electronic structure of disordered bcc Fe(x)Al(1-x) (0.4<x<0.75), Co(x)Al(1-x) and Ni(x)Al(1-x) (x=0.4; 0.5; 0.6) alloys near the 1:1 stoichiometry, as well as of the ordered B2 (FeAl, CoAl, NiAl)…
The bcc-based Fe_{1-x}Al_{x} exhibit interesting magnetic and anomalous structural properties as a function of composition and sample processing conditions arising from thermal or off-stoichiometric chemical disorder, and, although well…
Point defect species and concentrations in metastable Fe-C alloys are determined using density functional theory and a constrained free-energy functional. Carbon interstitials dominate unless iron vacancies are in significant excess,…
The elastic and magnetic properties, thermodynamical stability, deviation from stoichiometry and order/disorder transformations of phases that are relevant to Be alloys were investigated using density functional theory simulations coupled…
In the layered iron-based superconductor YFe2Ge2, a high Sommerfeld ratio of ~100 mJ/molK^2 and a T^(3/2) temperature dependence of the electrical resistivity at low temperature T indicate strong electronic correlations and point towards an…
Two intermetallic FeAl compounds with Al content of 70.68 and 72.17 at.pct were studied using M\"ossbauer spectroscopy (5 to 296 K) and X-ray diffraction (15 to 300 K). The compounds were found to crystallize in the orthorhombic Cmcm space…
The local structure of superconducting single crystals of K0.8Fe1.6+xSe2 with Tc = 32.6 K was studied by x-ray absorption spectroscopy. Near-edge spectra reveal that the average valence of Fe is 2+. The room temperature structure about the…
The presence of a point defect typically breaks the stoichiometry in a semiconductor. For example, a vacancy on an A-site in an AB compound makes the crystal B-rich. As the stoichiometry changes, so do the chemical potentials. While the…
The origin of the superior high-temperature strength of {\gamma}-TiAl with high Nb addition remains highly controversial, largely due to the unclear role of Nb atoms. Using large-scale hybrid Monte Carlo and molecular dynamics simulations…
From systematic ab initio calculations of the alloy system Mg_{1-x}Al_{x}B_2, we find a strong tendency for the formation of a superstructure characterized by Al-rich layers. We also present a simple model, based on calculated energies and…
Various intermetallic compounds harbor subtle electronic correlation effects. To elucidate this fact for the Fe-Al system, we perform a realistic many-body investigation based on the combination of density functional theory with dynamical…
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…
As a newly identified single-crystalline van der Waals dielectric with a high dielectric constant, Bi2SeO5 plays a pivotal role in advancing 2D electronic devices. In this work, we systematically investigate the defect properties of Bi2SeO5…
Using B2 MoTa, the strongest B2 former among group V/VI refractory binaries, as a model system, we compute temperature-dependent Gibbs energies of formation of vacancies and antisites from ab initio calculations up to 3000 K at the…
In BaFe2As2, structural and magnetic planar defects begin to proliferate below the structural phase transition, affecting descriptions of magnetism and superconductivity. We study using density-functional theory the stability and magnetic…
A thermodynamic model based on the law of mass action is used to calculate concentrations of elementary point defects and to determine site preferences of solute atoms in ordered alloys. Combinations of lattice vacancies, antisite atoms and…
Crystallographic defects in a topological semimetal can result in charge doping, and the scattering due to the defects may mask its exotic transport properties. Here, we investigate the possible crystallographic defects including vacancy…
The effects of various point defects and lattice distortions on the structural, electronic, and magnetic properties of Co$_2$MnAl alloy are investigated using density functional theory calculations. For the point defects, six types of…
We have studied intrinsic defect complexes in In$_2$O$_3$ using ab initio random structure searching (AIRSS). Our first-principles density-functional-theory calculations predict the thermodynamic stability of several novel defect…
Various experimental techniques, have revealed that the predominant intrinsic point defects in BaF$_2$ are anion Frenkel defects. Their formation enthalpy and entropy as well as the corresponding parameters for the fluorine vacancy and…