H+−H2Ocollisions studied by time-dependent density-functional theory combined with the molecular dynamics method

Abstract

${\mathrm{H}}^{+}\ensuremath{-}{\mathrm{H}}_{2}\mathrm{O}$ collisions are investigated using the time-dependent density-functional theory combined with the molecular dynamics method, in which the electrons are described quantum mechanically within the framework of time-dependent density-functional theory and the ionic cores are described classically by Newton's equations. The feedback between quantum electrons and classical ions is self-consistently coupled by Ehrenfest's method. The electron capture, electron loss, and ionization cross sections are obtained in the energy range of 1--1000 keV and excellent agreements are achieved with available experimental and theoretical data. The orientation effects of the ${\mathrm{H}}_{2}\mathrm{O}$ target are found to be significant in the collision processes, especially in low-energy collisions.