Electron-impact ionization and excitation cross sections of atoms with two outer-shell electrons

The binary encounter model incorporating exchange as developed by Vriens is used to calculate the cross sections for the excitation of the first excited singlet and triplet states of Hg, Cd and Zn, and the ionization cross sections for Hg, Cd, Zn, Ca, Mg and Be. For both excitation and ionization a quantal momentum distribution function for atomic electrons is used. The calculations are compared with the available experimental and theoretical results.