Dissociation of H2+ ion by collision-induced vibrational excitation

Abstract

Collision‐induced dissociation of hydrogen molecular ion due to the vibrational excitation from ground vibrational state to the continuum of electronic ground state (1sσ_g) has been studied, using sudden approximation. In close encounters, the interaction between the nucleus of projectile and the two nuclei of molecular ion has been taken as the sum of two screened Coulomb‐type interactions. Exact values for the ground vibrational state and quasiclassical wavefunctions for the continuum have been used. The angular distribution, energy distribution, and total vibrational dissociation cross section for fragments in a given excess energy range have been calculated with He, Ar, and Xe as projectiles. Cross sections for dissociation by Ar impact have been calculated for collision energies ranging from 3 to 50 keV, and for He and Xe at 10 keV. It is concluded that the electronic dissociation plays a dominant role even in the small excess energy region of dissociated fragments.