Electron-induced double ionization of oriented methane molecules

Abstract

We report here a theoretical study of the target orientation effect on the total cross sections for the double ionization of methane molecules impacted by electrons. The theoretical description is performed within the first Born approximation. The initial state of the collisional system is composed of an electron projectile modeled by a plane wave and a molecular target described by a one-center wave function while the final state is constituted by a scattered electron described by a plane wave and two ejected electrons both represented by a Coulomb wave and coupled with a Gamow factor. Secondary electron energetic distributions and total cross sections are reported for particular target configurations. Strong orientation effects on the double-ionization process are pointed out in particular when scrutinized orbital by orbital.