ANGULAR-DISTRIBUTIONS, ENERGY DISPOSAL, AND BRANCHING STUDIED BY PHOTOELECTRON-PHOTOION COINCIDENCE SPECTROSCOPY - O-2+ NO+, ICI+, IBR+, AND I2+ FRAGMENTATION

It is shown that some levels of the A 2Πu states of I2+, IBr+, and ICl+ are stable toward dissociation, and ought to decay by emission. The B 2Σ g+ state of I2+ is fully dissociated to ground state I+ +1, while the B 2Σ g+ states of IBr+ and ICl (probably) yield excited decay products. The c 3Π and B1Π states of NO+ dissociate to ground state N+ + O fragments, while the c 4Σg and 2Πu states of O2+ near 24 eV dissociate to excited levels of O + + O. The origin of anomalous time-of-flight peak shapes is discussed, and several examples are attributed to anisotropic fragment angular distributions. © 1979 American Institute of Physics.