The Dissociative Electroionization of Nitrous Oxide. The O+ Dissociation Channel.

By electroionization mass spectrometry and ion kinetic energy analysis, the O+ fragment ion formation from N2O has been analyzed. Different appearance energies are measured and interpreted. Between the onset at 15.27 eV and 22 eV only two dissociation limits are involved, i.e. O+(4S)+N2(X1Sigma+/g) at 15.29 eV and O+(2D)+N(X1Sigma+/g) at 18.61 eV. In both cases N2(X1Sigma+/g) is produced in its v=0 up to v=8 vibrational levels. Predissociation of ionic and Rydberg states of N2O are the dominant processes.