Molecular-Orbital Calculations on Inelastic Ne-Ne+Collisions

Abstract

A series of ab initio Hartree-Fock calculations have been performed for the systems ${\mathrm{Ne}}_2$, ${\mathrm{Ne}}_2^{+}$ and ${\mathrm{Ne}}_2^{++}$ for different values of the interatomic distance $R$. Satisfactory convergence was reached for $R\ge 1$ a. u. For $R<\mathrm{}1\mathrm{}$ a. u. molecular-orbital energies were determined from a united-atom approximation. From the total energies and from energies of occupied and nonoccupied orbitals approximated-diabatic-potential curves were obtained for a large number of excited states of the ${\mathrm{Ne}}_2^{+}$ system. The approximations used were checked by comparison with the results of open-shell Hartree-Fock calculations on ${\mathrm{Ne}}_2^{+}$. The potential-energy curves obtained show that there are energetical possibilities for new assignments of the inelastic energy losses observed in nonviolent Ne-${\mathrm{Ne}}^{+}$ collisions. These assignments are able to explain observations that cannot be described by the models proposed earlier.