Electronic spectroscopy of jet-cooled vinyl radical

The spectra of the X2A′-A2A″ electronic transition of jet-cooled vinyl radical, C2H3, and its partially deuterated isotopomer, CD2CH, have been obtained via action spectroscopy. The appearance of the H or D fragment was monitored via 1+1′ resonance enhanced multiphoton ionization through the Lyman-α transition. The vibrational structure of the A2A″ state was fully resolved and analyzed. The experimental vibrational frequencies agree well with ab initio calculations. The simulation of the rotational structure of several bands reinforces vibrational assignments.