Electron capture by partially stripped ions of C and N from ground state Na: a low-energy study

Abstract

The process of single-electron transfer from ground state Na to the incident ions of C 4+ and N 5+ has been investigated theoretically in the low-energy region (1 E 5 keV amu −1 ). Although both C 4+ and N 5+ possess identical He-like structure, their roles reveal very different collision dynamics. The semiclassical approximation in the molecular orbital formulation augmented with the proper electron translation factor, has been used to calculate both the partial and the total capture cross sections. A low-energy structure in C 4+ -Na has been observed, but for N 5+ -Na collisions the cross section remains a smoothly varying function of the impact energy. The possible underlying mechanism that leads to the low-energy structure in the C 4+ -Na process is discussed. Present total cross sections are compared with recent CTMC results.

Role of the projectile core in slow ion - molecule collisions: a molecular-state close-coupled treatment

“…At low energy our total capture cross section for C 4+ -Na exhibits a structure which agreed nicely with the experimental study of C 4+ -H [12]. The underlying mechanisms in producing the observed structures in the capture cross sections are alike in both cases; in our theoretical model they seem to emanate from the interplay of successive radial couplings among nearly degenerate -states in a localized region, a clear signature of the structured projectile (see [11]). This interesting finding provides further impetus to the investigation of the charge transfer mechanism in ion-molecule collisions; in particular, in the low-energy region there are not many studies.…”

“…The process of charge transfer becomes much more challenging as E gets lower (E 1 keV amu −1 ), where the capture is highly state selective. This motivated us to undertake a systematic study of the slow electron transfer from the pseudo-one-electron alkali target (Na) by C 4+ and N 5+ [11]. In addition to the total capture cross sections our calculation provided the -distribution as well.…”

“…He 2+ , Li 3+ , C 4+ and N 5+ ) should enable us to understand the possible role of the core structure, if any. We use our molecular-orbital (MO) approximation [11] to investigate the chargechanging reaction (1). The inter-nuclear movement is treated by a classical trajectory, whereas the action of the electron during the collision is considered quantum mechanically.…”

Role of initial orbital alignment in H++K(4p) collisions at low energies

“…At low energies the colliding pair can easily be treated as a transient diatomic molecule ; in the asymptotic region it will disintegrate into entrance and various final channels. This molecular orbital (MO) prescription has been successfully used over the last few years to investigate charge‐transfer processes involving ion atoms and ion molecules 15–19.…”

Charge exchange in C6++ H (1s) collisions at low energies

“…We have taken an initiative to investigate the low‐energy domain to fill that gap. The calculations reported here are based on an MO expansion method, which in recent years has been applied successfully to heavy‐particles scattering 19–27 at low energies. In this semiclassical approach a classic trajectory is considered for the movement of the nuclei whereas the motion of the electrons is treated quantum mechanically.…”