Crossed-beam study of the C(3PJ)+C2D2(X1Σg+) → C3D+D(2S1/2) reaction between 4 and 240 meV relative translational energy

The reaction C(3PJ)+C2D2(X1Σg+) → C3D+D(2S1/2) has been studied with pulsed, crossed, supersonic molecular beams, in the range of relative translational energies εtr=4–240 meV. The D(2S1/2) product has been detected by laser-induced fluorescence. The reaction is found to be slightly exoergic, with no barrier. Relative integral cross-sections are proportional to (εtr)−0.72±0.03 below εtr=50 meV. These findings, along with energetics considerations, suggest that the analogous C(3PJ)+C2H2(X1Σg+) → C3H+H(2S1/2) reaction is also a barrierless process.