On the Classical Trajectory Monte-Carlo Method to study ion-atom/molecule collisions.*

In this talk I will report our recent studies on ionization, electron capture and excitation in ion-atom and ion-molecule collisions at energies ranging between 10 keV u^-1 and 500 keV u^-1.

The need of accurate total and partial cross sections to model the impurity density plasmas has encouraged us to study A^q+ + H collisions of interest in fusion research. We have employed the CTMC approximation [1] to perform calculations between fully stripped ions and atomic hydrogen in ground and first excited states. The importance of the phase space initial distributions used in the description of H(1s) and H(n=2) targets will be pointed out and the cross sections for ionization and, state-selective electron capture and excitation, for the dominant channels, will be presented.

Besides, electron removal in ion-water collisions is the first step of the damage of biological systems by interaction with ions. A recent study [2] of collisions of Li³⁺ and C³⁺ ions with water molecules, in the framework of the independent electron approximation, using a three-center model potential for the electron-target interaction [3], will be also shown.

[1] R Abrines and I C Percival, Proc. Phys. Soc. 88, 861 (1966)

[2] C Illescas et al., Phys. Chem. Chem. Phys. 22, 19573 (2020)

[3] C Illescas et al., Phys. Rev. A 83 052704 (2011)