scholarly journals Ab initio моделирование энергии растворения и энергии связи водорода с 3sp-, 3d- и 4d-примесями в ОЦК-железе

2021 ◽  
Vol 63 (7) ◽  
pp. 830
Author(s):  
М.С. Ракитин ◽  
А.А. Мирзоев
Keyword(s):  
Density Functional Theory ◽  
Ab Initio ◽  
Density Functional ◽  
Theoretical Description ◽  
Atomic Level ◽  
Functional Theory ◽  
Bcc Iron ◽  
Fundamental Understanding ◽  
Substitutional Impurities ◽  
Hydrogen Dissolution

A fundamental understanding of the localization of H atoms in steel is an important step towards a theoretical description of the mechanisms of hydrogen embrittlement at the atomic level. Ab initio calculations within the framework of density functional theory (DFT) is used to investigate the effect of various substitutional impurities Mg, Al, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo , Pd and Cd on the energy of hydrogen dissolution in the lattice of bcc iron. The electronic and elastic contributions of various impurities to the dissolution energy are distinguished, and their influence on the binding energy of hydrogen and impurities is analyzed. The existence of a linear dependence of the energy of hydrogen dissolution on the magnitude of the change in the electron density of the intra-tetrahedral pore after the introduction of a hydrogen atom into it is shown. The results obtained made it possible to formulate the key mechanisms for controlling the localization of hydrogen in bcc iron by substitution impurities.

scholarly journals Interaction of sulfur with impurities in bcc iron

2021 ◽  
Vol 2103 (1) ◽  
pp. 012071
Author(s):  
A V Verkhovykh ◽  
A A Mirzoev ◽  
Yu K Okishev ◽  
N S Dyuryagina
Keyword(s):  
Density Functional Theory ◽  
Software Package ◽  
Density Functional ◽  
Functional Theory ◽  
The Third ◽  
Bcc Iron ◽  
The Density Functional Theory ◽  
Coordination Spheres ◽  
Strong Repulsion ◽  
Substitutional Impurities

Abstract In this work, the modeling of the sulfur interaction with substitutional impurities (Mn, P) and interstitial (C) has been carried out. All calculations were performed using the density functional theory in the WIEN2k software package. For the first two coordination spheres, there is a strong repulsion between carbon and sulfur, but in the third relative position, a slight attraction arises between the atoms. When sulfur interacts with manganese, attraction occurs only for the first coordination sphere, while the dissolution energy of both manganese and sulfur decreases. In the case of the S-P interaction, the binding energy is negative, and the dissolution energy of both sulfur and phosphorus decreases for all configurations, although the distance between phosphorus and sulfur increases. It can be assumed that the presence of phosphorus leads to the accumulation of sulfur in the material.

scholarly journals Hydrogen Trapping in bcc Iron

Materials ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2288 ◽  
Author(s):  
Anastasiia S. Kholtobina ◽  
Reinhard Pippan ◽  
Lorenz Romaner ◽  
Daniel Scheiber ◽  
Werner Ecker ◽  
...  
Keyword(s):  
Density Functional ◽  
Atomic Level ◽  
Body Centered Cubic ◽  
Hydrogen Trapping ◽  
Functional Theory ◽  
Bcc Iron ◽  
Ferromagnetic Body ◽  
Fundamental Understanding ◽  
Crystal Lattice Defects ◽  
Trapping Sites

Fundamental understanding of H localization in steel is an important step towards theoretical descriptions of hydrogen embrittlement mechanisms at the atomic level. In this paper, we investigate the interaction between atomic H and defects in ferromagnetic body-centered cubic (bcc) iron using density functional theory (DFT) calculations. Hydrogen trapping profiles in the bulk lattice, at vacancies, dislocations and grain boundaries (GBs) are calculated and used to evaluate the concentrations of H at these defects as a function of temperature. The results on H-trapping at GBs enable further investigating H-enhanced decohesion at GBs in Fe. A hierarchy map of trapping energies associated with the most common crystal lattice defects is presented and the most attractive H-trapping sites are identified.

scholarly journals Ab initio theory of noble gas atoms in bcc transition metals

2018 ◽  
Vol 20 (25) ◽  
pp. 17048-17058 ◽  
Author(s):  
Chao Jiang ◽  
Yongfeng Zhang ◽  
Yipeng Gao ◽  
Jian Gan
Keyword(s):  
Density Functional Theory ◽  
Transition Metals ◽  
Ab Initio ◽  
Density Functional ◽  
Noble Gas ◽  
Functional Theory ◽  
Ab Initio Theory ◽  
Fundamental Understanding

Systematic ab initio calculations based on density functional theory have been performed to gain fundamental understanding of the interactions between noble gas atoms (He, Ne, Ar and Kr) and bcc transition metals in groups 5B (V, Nb and Ta), 6B (Cr, Mo and W) and 8B (Fe).

scholarly journals Density Functional Theory and Complete Basis Set Ab Initio Computational Study of Five-, Six-, Seven- and Eight-hydrogen Coordinated Carbon Cations

1999 ◽  
Vol 23 (8) ◽  
pp. 502-503
Author(s):  
Branko S. Jursic
Keyword(s):  
Density Functional Theory ◽  
Ab Initio ◽  
Density Functional ◽  
Computational Study ◽  
Basis Set ◽  
Functional Theory ◽  
Complete Basis ◽  
Complete Basis Set ◽  
High Level

High level ab initio and density functional theory studies are performed on highly protonated methane species.

scholarly journals Ab initio molecular dynamics of hydrogen on tungsten surfaces

2021 ◽  
Author(s):  
Alberto Rodríguez-Fernández ◽  
Laurent Bonnet ◽  
Pascal Larrégaray ◽  
Ricardo Díez Muiño
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
Ab Initio ◽  
Density Functional ◽  
Ab Initio Molecular Dynamics ◽  
Dissociation Process ◽  
Functional Theory ◽  
Classical Molecular Dynamics ◽  
Hydrogen Molecules

The dissociation process of hydrogen molecules on W(110) was studied using density functional theory and classical molecular dynamics.

Flexoelectricity in atomic monolayers from first principles

Nanoscale ◽  
2020 ◽  
Author(s):  
Shashikant Kumar ◽  
David Codony ◽  
Irene Arias ◽  
Phanish Suryanarayana
Keyword(s):  
Density Functional Theory ◽  
Transition Metal ◽  
Ab Initio ◽  
First Principles ◽  
Density Functional ◽  
Transition Metal Dichalcogenides ◽  
Functional Theory ◽  
Group Iii ◽  
Flexoelectric Effect ◽  
Metal Dichalcogenides

We study the flexoelectric effect in fifty-four select atomic monolayers using ab initio Density Functional Theory (DFT). Specifically, considering representative materials from each of Group III monochalcogenides, transition metal dichalcogenides...

Germanene: a new electronic gas sensing material

RSC Advances ◽  
2016 ◽  
Vol 6 (104) ◽  
pp. 102264-102271 ◽  
Author(s):  
Sanjeev K. Gupta ◽  
Deobrat Singh ◽  
Kaptansinh Rajput ◽  
Yogesh Sonvane
Keyword(s):  
Density Functional Theory ◽  
Ab Initio ◽  
Electronic Properties ◽  
Structural Stability ◽  
Density Functional ◽  
Gas Sensing ◽  
Functional Theory ◽  
Adsorption Characteristics ◽  
Sensing Material ◽  
Gas Molecules

The structural stability and electronic properties of the adsorption characteristics of several toxic gas molecules (NH3, SO2 and NO2) on a germanene monolayer were investigated using density functional theory (DFT) based on an ab initio method.

Sign in / Sign up

Export Citation Format

Share Document