ON SOME STRUCTURAL-PROPERTIES OF VARIOUS ELECTRONIC STATES OF THE HYDROXONIUM ION

Calculations have been carried out for several excited electronic stat es of the protonated water molecule the hydroxonium ion H3O+ at the le vel of highly correlated, multireference double-excitation configurati on-interaction (MRD-CI) computations for several potential energy prof iles of the system. It was found that different structural geometries exist for the ground and for the excited electronic states and that su ch geometries are very helpful for a quantitative interpretation of pr evious mass spectrometric fragmentation patterns. The general features of the umbrella motion in several electronic slates are described for the title system and their importance for the analysis of the above s pectra is shown for the first time. The possible extension of the pres ent study to analyze charge-exchange and direct inelastic collision ex periments in molecular beams is briefly outlined.