Excited ions reaction scattering

The products of reactive ion-neutral collisions may be formed in a variety of excited states. Excited products from nonreactive collisions have already been discussed in a previous section. Theoretical calculations of vibrational excitation in the products of symmetric charge-transfer reactions have also been mentioned previously.312-314 The present section deals with excited products from reactive ion-neutral scattering, with special emphasis on luminescence measurements. 

The H3+ molecule ion is the simplest nonlinear molecule, of course, and its potential surface has been calculated in detail and with relatively high accuracy490 (see Figs. 63-65). This ab initio surface, as well as that for Li+-H2,491 have been employed in calculations of cross sections for vibrational excitation in nonreactive scattering collisions492 (see also Section II.B.2.b). An ab initio calculation of the vibrational spectrum of H3+ has also been carried out,207 and it has been suggested that vibrational chemiluminescence should be observable from the reaction H2+ (H2, H)H3+. 

The basic processes which are responsible for reaction on irradiation of these covalent inorganic systems involve excitation and ionization of the molecules by the secondary electrons generated in the sample by Compton scattering. The primary species produced are excited molecule ions... 

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