Fragmentation of water molecules by He2+ and Li3+ impact

J. M. MONTI; M. A. QUINTO; R. D. RIVAROLA; P. N. TEREKHIN; O. A. FOJÓN

Palm Cove

Simposio; The International Symposium on (e,2e), Double Photo-ionization and Related Topics and the 19th International Symposium on Polarization and Correlation in Electronic and Atomic Collisions; 2017

Investigation of single and multiple-electron removalprocesses occurring between fully stripped ions and simple molecules is offundamental interest in many areas such as nuclear fusion [1], plasma physics[2] and others. In particular, collisions of ions with H2O are of principalinterest in biology and medicine [3]. The ionization of water molecules producedifferent charged species, which can damage the surrounding cells. Therefore,it is important to calculate cross sections of pure ionization, capture andtransfer-ionization reactions to determine their contributions to the fragmentationprocesses. The aim of the present investigation is focused on theoreticalcalculations of fragmentation cross sections for water molecules interactingwith He2+ and Li3+ ions, based on the model proposed inthe work [4]. We use the three-body Continuum Distorted Wave-Eikonal InitialState approximation (3B-CDW-EIS) [5] to obtain the cross sections. The initialwavefunctions of the active electrons bound to a particular water molecularorbital are described employing the complete neglect of the differentialoverlap (CNDO) approximation [6]. A trinomial distribution analysis has beenemployed to compute exclusive probabilities using the independent electron(IEL) model. A unitarization procedure is employed to avoid overestimations of3B-CDW-EIS impact parameter probabilities. We compare our results just with previouscalculations, because to our knowledge no experimental data exist for thesesystems. Fragmentation cross sections for the case of He2+ on H2Ocollisions are shown in Figure 1. The developed approach may be used to investigatefragmentation patterns of more complex molecules.