Electronic spectroscopy of jet-cooled vinyl radical

The spectra of the (X) over tilde (2)A'-(A) over tilde (2)A" electronic tra nsition of jet-cooled vinyl radical, C2H3, and its partially deuterated iso topomer, CD2CH, have been obtained via action spectroscopy. The appearance of the H or D fragment was monitored via 1+1' resonance enhanced multiphoto n ionization through the Lyman-alpha transition. The vibrational structure of the (A) over tilde (2)A" state was fully resolved and analyzed. The expe rimental vibrational frequencies agree well with ab initio calculations. Th e simulation of the rotational structure of several bands reinforces vibrat ional assignments. (C) 2001 American Institute of Physics.