Unimolecular dissociation rate constants: chlorobenzene cations revisited by using a new method

Abstract

Unimolecular dissociation rates of metastable molecular ions formed at the laser focus of a time-of-flight mass spectrometer (TOFMS) have been determined by measuring the relative concentrations of «parent» metastable ions and the «daughter» fragment ions as a function of their retained kinetic energies upon dissociation. This is accomplished by the use of a simple one-stage ion mirror/energy analyzer. For a given reflection potential on the ion mirror, only those ions with a kinetic energy equal to or less than the reflection potential are detected