Knowledge Bank

Precise molecular constants of the CH$2$CHS (vinylthio) radical in the ground vibronic level were determined by Fourier-transform microwave (FTMW) and FTMW-millimeter wave double-resonance spectroscopy}, \textit{J. Chem. Phys.} \underline{\textbf{123}}, 054324 (2005).}. The \textit{\ {B}} -- \textit{\ {X}} electronic transition of CH$2$CHS was observed by LIF spectroscopy. Rotational constants in the upper electronic state were determined from a rotationally resolved LIF excitation spectrum of jet-cooled CH$2$CHS. A dispersed fluorescence spectrum from the zero-vibtational level of the \textit{\ {B}} state was also measured to determine vibrational frequencies in the ground electronic state. The experimental molecular constants were compared with results of \textit{ab initio} calculations.