Knowledge Bank

Vinyl radical, C$2$H$3$, is a transient but fundamental hydrocarbon species which plays important roles in a number of combustion processes. Previous high resolution spectroscopic studies of this species have been very limited; only the CH$2$ wagging mode in the electronic ground state has been } studied with IR diode laser absorption methods. Guided by both recent time-resolved FTIR emission } and high level density functional predictions, we have recently used the slit jet discharge IR laser spectrometer to observe and assign high-resolution infrared spectra of jet-cooled vinyl radical in the symmetric CH$2$ stretch region. In addition to structural information, the tunneling dynamics due to in-plane rocking of the $\alpha$-C-H will be discussed.