Coordinate space translation technique for simulation of electronic process in the ion–atom collision

Abstract

Recently we developed a theoretical model of ion-atom collisions, which was made on the basis of a time-dependent density functional theory description of the electron dynamics and a classical treatment of the heavy particle motion. Taking advantage of the real-space grid method, we introduce a "coordinate space translation" technique to allow one to focus on a certain space of interest such as the region around the projectile or the target. Benchmark calculations are given for collisions between proton and oxygen over a wide range of impact energy. To extract the probability of charge transfer, the formulation of Lüdde and Dreizler [J. Phys. B 16, 3973 (1983)] has been generalized to ensemble-averaging application in the particular case of O((3)P). Charge transfer total cross sections are calculated, showing fairly good agreements between experimental data and present theoretical results.

Theoretical investigation of He2+-Ar collisions in the energy range of 4–300 keV/amu

“…The TDDFT method has been described thoroughly in previous works [17][18][19] and we only briefly discuss it here. In principle, all dynamic information of ion-atom collisions can be obtained by using the TDSE method.…”

A theoretical model for electron transfer in ion–atom collisions: Calculations for the collision of a proton with an argon atom

“…Our results do not change if the absorbing boundary are varied over a reasonable range. In the CST [29] technique, all contents in the simulation box have been overall translated in order to make the projectile to remain at the center of the simulation box when it departs from the target in collision process. The crucial point is that we use a larger grid, where the simulation box is enclosed, with the same spacing, and assign the wave function as the value zero at the points outside the simulation box.…”

“…In the present contribution, taking advantage of the real-space grid method, we include a "coordinate space translation" (CST) technique [29], which is ideally suited to study electron transfer process of collisions. Benchmark calculations are given for collisions between proton and argon over a wide range of impact energy.…”

Theoretical study of the channeling effect in the electronic stopping power of silicon carbide nanocrystal for low-energy protons and helium ions

“…The interval of time step is $10 À3 fs, which is adjustable for different velocities to conserve the total energy during the collision. In order to avoid artificial reflections of the electronic wavefunctions from the boundaries in the collision processes, we have added the complex absorbing potential [47] at the boundaries of the simulation box, which can absorbs the outgoing waves.…”