Knowledge Bank

We present the branching ratios for v = 2 and v = 1 levels of the HF fragment after photo dissociation of $N=v1+v2=3$ bands of $(HF)2$ and v=3 HF stretch of HFHCl. The molecular complexes are produced in super-sonic jets which are intracavity in a Ti:Sapphire ring laser to exploit the high power necessary for pumping weak overtone transitions. The HF submolecule at v = 3 has vibrational excitation which is $104$ $cm-1$ in excess of the binding energy of the complex resulting in the rupture of the van-der-Waals bond, and the excess energy is distributed among the vibration-rotation-translational degrees of freedom of the fragments. The $\Delta v=1$ and $\Delta v=2$ emission from the HF fragment are then detected by large area PbS and Ge detectors, respectively. For the bands presently examined $v1=3,v2=0$ of $(HF)2$ and the analogous band of HFHCl, the channel with the HF fragment in the v=2 level is the more dominant one, as expected from $\Delta v=-1$ propensity rules.