Acceleration effects in slow ion-atom collisions from a first-principles dynamics

B. Thorndyke, D. A. Micha, Keith A Runge

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Slow ion-atom collisions can be described within a first-principles molecular dynamics based on eikonal wave functions for the nuclei and the time- dependent Hartree-Fock (TDHF) approximation for electrons that self-consistently couples the electronic and nuclear degrees of freedom. By expanding the molecular Orbitals in traveling atomic orbitals containing electron translation factors, it is possible to eliminate spurious couplings between same-center orbitals at asymptotic distances, and this generates a term in the density matrix equations proportional to the nuclear accelerations. We examine the effect of this acceleration term on Löwdin atomic populations for H+ + H(1s) and He2+ + H(1s) collisions, for varying collision energies and impact parameters. We find significant increases in atomic populations for an intermediate range of energies going from several tens to several hundreds of electron volts, and for low impact parameters, in the case of the H+ + H(1s) collision.

Original languageEnglish (US)
Pages (from-to)361-366
Number of pages6
JournalInternational Journal of Quantum Chemistry
Volume75
Issue number4-5
StatePublished - 1999
Externally publishedYes

Fingerprint

Heavy ions
Atoms
collisions
Electrons
Hartree approximation
atoms
ions
Molecular orbitals
Wave functions
electron orbitals
Molecular dynamics
molecular orbitals
electrons
degrees of freedom
wave functions
molecular dynamics
orbitals
nuclei
energy
electronics

Keywords

  • Density matrix
  • Quantum molecular dynamics
  • Time-dependent Hartree-Fock

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

Acceleration effects in slow ion-atom collisions from a first-principles dynamics. / Thorndyke, B.; Micha, D. A.; Runge, Keith A.

In: International Journal of Quantum Chemistry, Vol. 75, No. 4-5, 1999, p. 361-366.

Research output: Contribution to journalArticle

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