Temperature dependence of resonant isotopic vibrational energy transfer in H35Cl–H37 Cl

The resonant vibration-to-vibration energy transfer process, H35Cl(v=1)+H37Cl(v=0) ?H35Cl(v=0) +H37Cl(v=1)+ΔE=2.1 cm−1 has been investigated over the temperature range 192–632 K by use of an isotopically selective transverse discharge chemical laser and infrared fluorescence techniques. The transfer probability shows a temperature dependence of PVV∼T−1.6 over the range studied. This dependence is similar to those observed for a number of other near-resonant processes, but differs from current theoretical predictions for resonant vibrational energy transfer. It is shown that a model based on a statistical distribution of rotational states resulting after a long-lived collision is useful in understanding the parameters which must be important in resonant vibrational energy transfer.