Die kinetische Energie ionisierter Molekülfragmente

Abstract

Several authors have observed the dissociation of a doubly charged CO2 + ion into CO+ and O+. There exist, however, discrepancies with respect to the transition energy (total translational energy). Therefore, the initial energy of O+ and CO+ ions formed by electron impact in CO2 has been reinvestigated by the deflection method. Assuming dissociation into two fragments only, the transition energy can be calculated. In the initial energy distribution function of both ions a well pronounced satellite peak corresponding to the same transition energy of 5.5 eV is observed. This is interpreted as being due to the dissociation of a doubly charged CO2 + ion into two singly charged ions. The analogous dissociation of a metastable CO2 + ion is responsible for broad peaks at mass numbers 11.6 and 35.6 in the CO2 mass spectrum. From the peak width a transition energy between 5 and 6 eV is calculated, indicating that the same excited state of CO2 + may be involved in both decomposition reactions