Measurement of the rate constant k(E) of the unimolecular H₂ elimination from ethane radical cations in a reflectron mass spectrometer

A brief review of the literature concerning the H 2 loss reaction from ethane radical cations is given. The reaction most likely proceeds by tunneling of H atoms through a transfer barrier. In this contribution a new experimental approach is presented, which combines the high energy resolution of a zero kinetic energy (ZEKE) electron spectrometer with the high kinetic resolution of a reflecting ion time of flight spectrometer in a coincidence experiment. With this technique it is possible to measure the rate constant k ( E ) of the title reaction an ion energy resolution of 10 meV directly over three orders of magnitude. The implementation of this technique will ultimately enable the study of D 2 loss from isotopically labeled ethane‐d6 cations.