G. N. Ogurtsov

Ionization in simple quasimolecules: HeH22+?(He2+?+?H2)

Energy spectra of electrons ejected into 3He2+?H2?collisions have been measured in the incident ion energy range 6?30?keV. Parameters of the quasimolecule formed during the collision are determined. The dominant role of the channel (2a?)2?? 1a?3a? ? 1a??+?e in the production of electrons at keV ion energies has been revealed. The structure associated with autoionization transitions in the projectile helium atoms shows enormously large broadening and shift to lower energies.

Direct ionization in diatomic and triatomic quasimolecules

Recent experimental results on direct ionization in slow ion‐atom and ion‐molecule collisions are discussed on the basis of a quasimolecular approximation. It is shown that the parameters of the quasimolecules formed in slow collisions can be determined from analysis of experimental data on the energy spectra of the ejected electrons. The data obtained on parameters characterizing the analytical features of the energy surfaces of quasimolecules consisting of two and more atoms are presented.

Direct ionization of the molecules CO and CO2 by proton impact

Energy spectra of electrons ejected in H+ – CO and H+ – CO2 collisions have been measured in the electron energy range 5–50 eV and in the proton energy range 3–15 keV. The parameters of the diabatic term responsible for direct ionization have been determined. It has been shown that in the process of direct ionization the incident proton forms a quasimolecule with carbon atom rather than with oxygen atom or with the whole target molecule. The information obtained allowed establishing the chemical bonding in the target molecules.