Study of Unimolecular Reactions by Coulomb Explosion Imaging: The Nondecaying Vinylidene

Abstract

Isomerization of a highly excited vibrational state of acetylene was studied using the Coulomb explosion imaging technique. A vinylidene isomer was prepared by electron photodetachment of the negative molecular ion and the corresponding distribution function of the nuclear configurations of the molecule was sampled after a time period of $3.5\ensuremath{\mu}\mathrm{s}$. The population of the vinylidene isomer was found to be significantly high ( $\ensuremath{\sim}50%$), in contrast to the commonly accepted notion of vinylidene as a short-lived isomer.