Single ionization of CH4 by bare ions: Fully differential cross sections

A theoretical study of fully differential cross sections for the single ionization of CH4 by collisions with H+, He2+, and C6+ ions at energies in the order of MeV/amu is presented. We work in terms of the Born-3DW model, which considers a non-Coulomb central potential for the interaction of the active electron with the molecular core. Results obtained with the Born-3DW model are compared to those obtained with the Born-C3 model, which assumes this potential as purely Coulombic. The anisotropic potential of the CH4 molecule is smoothed through an angular integration, and results are averaged over all the possible orientations of the target molecule. Results for the lesser bound molecular orbitals (1T and 2A1) are presented and discussed for different projectile momentum transfers for the coplanar geometry.