H+ (D+, T+)–beryllium collisions studied using time-dependent density functional theory

Zhao, Shijun; Kang, Wei; Xue, Jianming; Zhang, Xitong; Zhang, Ping

doi:10.1016/j.physleta.2014.11.008

Cited by 11 publications

(13 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The non-equilibrium feature of electrons can be captured when the time-dependent dynamics of electrons is included faithfully. However, preceding attempts to do this on the level of the time-dependent density functional theory (TD-DFT) [30][31][32] have shown that this approach is extremely computationally costly. Practically, it is only capable to include tens of atoms in the calculation, which is far less than the required number of atoms to describe the propagation of shock waves.…”

Section: Introductionmentioning

confidence: 99%

Molecular dynamics simulation of strong shock waves propagating in dense deuterium, taking into consideration effects of excited electrons

et al. 2017

Self Cite

View full text Add to dashboard Cite

We present a molecular dynamics simulation of shock waves propagating in dense deuterium with the electron force field method [J. T. Su and W. A. Goddard, Phys. Rev. Lett. 99, 185003 (2007)], which explicitly takes the excitation of electrons into consideration. Non-equilibrium features associated with the excitation of electrons are systematically investigated. We show that chemical bonds in D 2 molecules lead to a more complicated shock wave structure near the shock front, compared with the results of classical molecular dynamics simulation. Charge separation can bring about accumulation of net charges on the large scale, instead of the formation of a localized dipole layer, which might cause extra energy for the shock wave to propagate. In addition, the simulations also display that molecular dissociation at the shock front is the major factor corresponding to the "bump" structure in the principal Hugoniot. These results could help to build a more realistic picture of shock wave propagation in fuel materials commonly used in the inertial confinement fusion.

show abstract

Section: Introductionmentioning

confidence: 99%

Molecular dynamics simulation of strong shock waves propagating in dense deuterium, taking into consideration effects of excited electrons

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…We follow the impact parameter approximation , to calculate the ECCS for the proton, given by σ c = 2 π ∫ p c ( b ) b .25em normald italicb where b is the proton impact parameter and p c ( b ), p c ( b ) = prefix∫ V false′ true| φ ( r , b , t ) false| 2 .25em normald 3 r is defined as the charge in a certain volume V ′ around the proton after the collision. |φ( r , b, t)| 2 is the charge density in the volume d 3 r , which is a cube with sides equal to the grid spacing.…”

Section: Methodsmentioning

confidence: 99%

“…The Octopus code was used for carrying out DFT and TDDFT calculations. 19−21 We follow the impact parameter approximation 11,14 to calculate the ECCS for the proton, given by…”

Section: ■ Methodsmentioning

confidence: 99%

“…In the LDA, the potential is locally approximated by the exchange-correlation energy of a homogeneous electron gas (HEG). 15 In Zhao et al, 14 the ECCS for the proton colliding with the helium atom in an energy region of 1−500 keV was calculated. Zhao et al showed that the LDA is not accurate enough in the 1−50 keV region, as the use of the Optimized Effective Potential (OEP) method is necessary.…”

Section: ■ Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Time-Dependent Density-Functional Theory for Determining the Electron-Capture Cross Section for Protons Impacting on Atoms and Molecules

et al. 2023

View full text Add to dashboard Cite

The use of the Time-Dependent Density-Functional Theory (TDDFT) has increased in the atomic collision field. Calculating the electron-capture cross section (ECCS) for protons is an important question in hadrontherapy and plasma physics, among other areas. In previous studies, it was shown that the approach based on the Local Density Approximation (LDA) fails in the 1−50 keV region, requiring the use of the Optimized Effective Potential (OEP) method. In this work, the ECCS values for 1−50 keV protons impacting on isolated hydrogen, carbon, nitrogen, oxygen, and nitrogenous atoms were determined using the TDDFT. It is shown that adding the Self Interaction Correction to the LDA (LDA-Sic) allows obtaining results close to those provided by the OEP and experiments, with the advantage that the LDA-Sic consumes less computational time. In addition, it was demonstrated that it is imperative to include the spin correction for the specific helium and oxygen cases, in order to get good results for the ECCS using the TDDFT. Theoretical results obtained in this work show excellent agreement with experimental values.

show abstract

“…electronic friction [130][131][132][133][134][135], model Hamiltonians [136][137][138][139][140], or time-dependent density functional theory (TDDFT) [141][142][143][144][145]. Furthermore, also ion-atom collisions [146] and ions impinging onto a metal cluster [147,148], colliding with carbon nanostructures [149], graphene fragments [150], graphene or boron nitride (BN) [14,151], the collision of Cl, Cl − with a MoSe 2 monolayer [152] as well as the electronic stopping of atoms or ions moving through a solid [153][154][155][156][157] have been simulated using TDDFT.…”

Section: B Time-dependent Dftmentioning

confidence: 99%

Towards an integrated modeling of the plasma-solid interface

Bönitz

Filinov

Abraham

et al. 2019

Front. Chem. Sci. Eng.

View full text Add to dashboard Cite

Solids facing a plasma are a common situation in many astrophysical systems and laboratory setups. Moreover, many plasma technology applications rely on the control of the plasma-surface interaction, i.e. of the particle, momentum and energy fluxes across the plasma-solid interface. However, presently often a fundamental understanding of them is missing, so most technological applications are being developed via trial and error. The reason is that the physical processes at the interface of a low-temperature plasma and a solid are extremely complex, involving a large number of elementary processes in the plasma, in the solid as well as fluxes across the interface. An accurate theoretical treatment of these processes is very difficult due to the vastly different system properties on both sides of the interface: quantum versus classical behavior of electrons in the solid and plasma, respectively; as well as the dramatically differing electron densities, length and time scales. Moreover, often the system is far from equilibrium. In the majority of plasma simulations surface processes are either neglected or treated via phenomenological parameters such as sticking coefficients, sputter rates or secondary electron emission coefficients. However, those parameters are known only in some cases and with very limited accuracy. Similarly, while surface physics simulations have often studied the impact of single ions or neutrals, so far, the influence of a plasma medium and correlations between successive impacts have not been taken into account. Such an approach, necessarily neglects the mutual influences between plasma and solid surface and cannot have predictive power.In this paper we discuss in some detail the physical processes a the plasma-solid interface which brings us to the necessity of coupled plasma-solid simulations. We briefly summarize relevant theoretical methods from solid state and surface physics that are suitable to contribute to such an approach and identify four methods. The first are mesoscopic simulations such as kinetic Monte Carlo (KMC) and molecular dynamics (MD) that are able to treat complex processes on large scales but neglect electronic effects. The second are quantum kinetic methods based on the quantum Boltzmann equation that give access to a more accurate treatment of surface processes using simplifying models for the solid. The third approach are ab initio simulations of surface process that are based on density functional theory (DFT) and time-dependent DFT. The fourths are nonequilibrium Green functions that able to treat correlation effects in the material and at the interface. The price for the increased quality is a dramatic increase of computational effort and a restriction to short time and length scales. We conclude that, presently, none of the four methods is capable of providing a complete picture of the processes at the interface. Instead, each of them provides complementary information, and we discuss possible combinations. PACS numbers:

show abstract

H+ (D+, T+)–beryllium collisions studied using time-dependent density functional theory

Cited by 11 publications

References 56 publications

Molecular dynamics simulation of strong shock waves propagating in dense deuterium, taking into consideration effects of excited electrons

Molecular dynamics simulation of strong shock waves propagating in dense deuterium, taking into consideration effects of excited electrons

Time-Dependent Density-Functional Theory for Determining the Electron-Capture Cross Section for Protons Impacting on Atoms and Molecules

Towards an integrated modeling of the plasma-solid interface

Contact Info

Product

Resources

About