First-Principles Calculation of Hydrogen Effects on the Formation and Diffusion of Vacancies in Alpha Iron: Discussion of the Hydrogen-Enhanced Strain-Induced Vacancy Mechanism

ABSTRACTWe have evaluated phosphorus (P) segregation in ion-irradiated nickel (Ni) by the rate theory model incorporating the results of first principles calculations. We find from our first principles calculation that the transport of P via the rotation mode of a mixed-dumbbell is unlikely to occur, and the transport coefficient of phosphorus by the vacancy mechanism is much larger than that reported previously. On the basis of our first principles results, we have also proposed to include the effect of free migration of P via the octahedral interstitial site of FCC Ni crystal in the rate theory model. With all these renewed parameters, we have successfully obtained the P distribution in irradiated Ni, which is very close to experiment, by adjusting the effect of P transport by the vacancy mechanism.

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Interaction between Substitutional and Interstitial Elements in α iron Studied by First-principles Calculation

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.46.1140 ◽

2005 ◽

Vol 46 (6) ◽

pp. 1140-1147 ◽

Cited By ~ 10

Author(s):

Hideaki Sawada ◽

Kazuto Kawakami ◽

Masaaki Sugiyama

Keyword(s):

First Principles ◽

First Principles Calculation ◽

Alpha Iron ◽

Interstitial Elements

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First-Principles Calculation of Lithium Adsorption and Diffusion on Silicene

Chinese Physics Letters ◽

10.1088/0256-307x/30/1/017103 ◽

2013 ◽

Vol 30 (1) ◽

pp. 017103 ◽

Cited By ~ 17

Author(s):

Juan Huang ◽

Hong-Jin Chen ◽

Mu-Sheng Wu ◽

Gang Liu ◽

Chu-Ying Ouyang ◽

...

Keyword(s):

First Principles ◽

First Principles Calculation ◽

And Diffusion

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First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge (001) surfaces

MRS Proceedings ◽

10.1557/proc-749-w20.10 ◽

2002 ◽

Vol 749 ◽

Author(s):

A. van de Walle ◽

M. Asta ◽

P. W. Voorhees

Keyword(s):

First Principles ◽

Self Assembly ◽

Compressive Strain ◽

Fold Increase ◽

Characteristic Size ◽

Activation Energies ◽

First Principles Calculation ◽

Reconstructed Surfaces ◽

Surface Increase ◽

And Diffusion

ABSTRACTFirst-principles calculations are used to calculate the strain dependencies of the binding and diffusion-activation energies for Ge adatoms on both Si(001) and Ge(001) c(4×2) reconstructed surfaces. Our calculations reveal that over the range of strains typically sampled during quantum dot self-assembly (0 to 1% compressive strain) the binding and activation energies on a strained Ge(001) surface increase and decrease, respectively, by 0.21 eV and 0.12 eV. For a growth temperature of 600 °C, these strain-dependencies give rise to a 16-fold increase in adatom density and a 5-fold decrease in adatom diffusivity in the region of compressive strain surrounding a Ge island with a characteristic size of 10 nm lying on top of a Si substrate covered by a Ge wetting layer.

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Influence of Nickel Addition on the Stability, Trapping, and Diffusion Behaviour of Hydrogen in Vanadium: A First-Principles Investigation

10.21203/rs.3.rs-143116/v1 ◽

2021 ◽

Author(s):

Jiayao Qin ◽

Zhigao Liu ◽

Wei Zhao ◽

Dianhui Wang ◽

Yanli Zhang ◽

...

Keyword(s):

First Principles ◽

Effective Means ◽

Interstitial Site ◽

First Principles Calculation ◽

Hydrogen Energy ◽

Ni Doping ◽

Octahedral Interstitial Site ◽

The Stability ◽

And Diffusion ◽

Diffusion Behaviour

Abstract Hydrogen embrittlement causes deterioration of materials used in hydrogen energy systems. Alloying is an effective means for overcoming this issue. In this study, the first-principles calculation method was used to investigate the effects of alloying Ni on the stability, dissolution, trapping, and diffusion behaviour of interstitial/vacancy H atoms in V. The calculated phonon spectra and solution energies of the vacancy/interstitial H atoms revealed that the V–Ni phase was dynamically and thermodynamically stable, and Ni addition could reduce the stability of V hydrides and improve their resistance to H embrittlement. H atoms in the interstitials and vacancies preferentially occupied the tetrahedral interstitial site (TIS) and octahedral interstitial site (OIS) with the lowest solution energies and diffused along the TIS → TIS and OIS → OIS paths with the minimum diffusion barrier energies. The trapping energy of the vacancy H atoms indicated that the addition of Ni could reduce the H trapping capability of the vacancies and suppress the retention of H in V. Detailed analysis of the calculated H diffusion barriers indicated that the presence of monovacancy defects blocked the diffusion of H atoms more than the presence of interstitials, and Ni doping did not enhance the H diffusion coefficient.

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First-principles calculation of hydrogen adsorption and diffusion on Mn-doped Mg 2 Ni (010) surfaces

Applied Surface Science ◽

10.1016/j.apsusc.2017.07.006 ◽

2017 ◽

Vol 425 ◽

pp. 148-155 ◽

Cited By ~ 10

Author(s):

Ziying Zhang ◽

Jiarui Jin ◽

Huizhen Zhang ◽

Xiaoxiao Qi ◽

Yang Bian ◽

...

Keyword(s):

First Principles ◽

Hydrogen Adsorption ◽

First Principles Calculation ◽

And Diffusion ◽

Mn Doped

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The performance of adsorption, dissociation and diffusion mechanism of hydrogen on the Ti-doped ZrCo(110) surface

Physical Chemistry Chemical Physics ◽

10.1039/c9cp02491c ◽

2019 ◽

Vol 21 (23) ◽

pp. 12597-12605 ◽

Cited By ~ 5

Author(s):

Qingqing Wang ◽

Xianggang Kong ◽

Huilei Han ◽

Ge Sang ◽

Guanghui Zhang ◽

...

Keyword(s):

First Principles ◽

Diffusion Mechanism ◽

First Principles Calculation ◽

And Diffusion ◽

Diffusion Of Hydrogen

Compared with pristine ZrCo(110), the adsorption, dissociation, and successive diffusion of hydrogen on the Ti-decorated ZrCo(110) have been investigated based on first-principles calculation.

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